refactor!: demote chime-validation-max-retries to private defvar

This is an internal startup-timing parameter, not a knob real users have
reason to tune through `M-x customize'. I demoted it from defcustom to
defvar and renamed it to `chime--validation-max-retries' to make the
private status explicit. Anyone who was overriding it can keep doing so
with `setq' (the variable still exists, just under the new name).

The three customize-time validation tests went away with the defcustom —
nothing left to validate at customize-time once it stops being a
customize-target. The setter helper still applies to the other five
numeric defcustoms.

Test files that referenced the variable (`test-chime-validation-retry.el',
`test-integration-chime-mode.el') were renamed mechanically along with
the source.

Breaking change: `(setq chime-validation-max-retries N)' becomes
`(setq chime--validation-max-retries N)' if you actually had it. Most
users won't have touched it.

4 files changed, 25 insertions, 52 deletions

diff --git a/chime.el b/chime.el
index 930a067..e843537 100644
--- a/chime.el
+++ b/chime.el
@@ -628,24 +628,15 @@ has elapsed.  This gives startup hooks time to populate org-agenda-files.")
 Reset to 0 when validation succeeds.  Used to provide graceful retry
 behavior for users with async org-agenda-files initialization.")
 
-(defcustom chime-validation-max-retries 3
+(defvar chime--validation-max-retries 3
   "Maximum number of times to retry validation before showing error.
-When org-agenda-files is empty on startup, chime will retry validation
-on each check cycle (every `chime-check-interval' seconds) until either:
-  - Validation succeeds (org-agenda-files is populated)
-  - This retry limit is exceeded (error is shown)
+When `org-agenda-files' is empty on startup, chime will retry validation
+on each check cycle (every `chime-check-interval' seconds) until either
+validation succeeds or this retry limit is exceeded.
 
-This accommodates users with async initialization code that populates
-org-agenda-files after a delay (e.g., via idle timers).
-
-Set to 0 to show errors immediately without retrying.
-Default is 3 retries (with 30-60s check intervals, this gives ~1.5-3 minutes
-for org-agenda-files to be populated)."
-  :type 'integer
-  :group 'chime
-  :set (lambda (symbol value)
-         (chime--validate-integer-setting symbol value 0 nil)
-         (set-default symbol value)))
+This is internal because no user has reason to tune the defensive
+startup-timing window through Customize.  If you need to override the
+default for a specific environment, `setq' the variable in your init.")
 
 (defvar chime-modeline-string nil
   "Modeline string showing next upcoming event.")
@@ -1852,7 +1843,7 @@ Returns nil if validation failed and check should be skipped."
       (if (cl-some (lambda (i) (eq (car i) :error)) issues)
           (progn
             (setq chime--validation-retry-count (1+ chime--validation-retry-count))
-            (if (> chime--validation-retry-count chime-validation-max-retries)
+            (if (> chime--validation-retry-count chime--validation-max-retries)
                 (progn
                   (let ((errors (cl-remove-if-not (lambda (i) (eq (car i) :error)) issues)))
                     (chime--log-silently "Chime: Configuration validation failed with %d error(s) after %d retries:"
@@ -1866,12 +1857,12 @@ Returns nil if validation failed and check should be skipped."
                   (chime--set-modeline-error-state "Configuration error — check *Messages* buffer"))
               (message "Chime: Waiting for org-agenda-files to load... (attempt %d/%d)"
                        chime--validation-retry-count
-                       chime-validation-max-retries)
+                       chime--validation-max-retries)
               ;; Update modeline tooltip to show waiting state
               (chime--set-modeline-error-state
                (format "Waiting for org-agenda-files... (attempt %d/%d)"
                        chime--validation-retry-count
-                       chime-validation-max-retries)))
+                       chime--validation-max-retries)))
             nil)
         (setq chime--validation-done t)
         (setq chime--validation-retry-count 0)
diff --git a/tests/test-chime-numeric-defcustom-setters.el b/tests/test-chime-numeric-defcustom-setters.el
index 03d7810..7fb5afa 100644
--- a/tests/test-chime-numeric-defcustom-setters.el
+++ b/tests/test-chime-numeric-defcustom-setters.el
@@ -161,26 +161,8 @@
                    'chime-max-consecutive-failures -1)
                   :type 'user-error)))
 
-;;;; chime-validation-max-retries — integer >= 0
-
-(ert-deftest test-chime-validation-max-retries-accepts-zero ()
-  "Normal: 0 means show errors immediately without retrying (per docstring)."
-  (let ((chime-validation-max-retries 3))
-    (customize-set-variable 'chime-validation-max-retries 0)
-    (should (= 0 chime-validation-max-retries))))
-
-(ert-deftest test-chime-validation-max-retries-accepts-positive ()
-  "Normal: positive integer is valid."
-  (let ((chime-validation-max-retries 3))
-    (customize-set-variable 'chime-validation-max-retries 5)
-    (should (= 5 chime-validation-max-retries))))
-
-(ert-deftest test-chime-validation-max-retries-rejects-negative ()
-  "Error: negative retry count is meaningless."
-  (let ((chime-validation-max-retries 3))
-    (should-error (customize-set-variable
-                   'chime-validation-max-retries -1)
-                  :type 'user-error)))
+;; Note: `chime--validation-max-retries' was demoted from defcustom to
+;; defvar in 0.8 — no customize-time setter, no validation tests here.
 
 (provide 'test-chime-numeric-defcustom-setters)
 ;;; test-chime-numeric-defcustom-setters.el ends here
diff --git a/tests/test-chime-validation-retry.el b/tests/test-chime-validation-retry.el
index b4e886c..70188bc 100644
--- a/tests/test-chime-validation-retry.el
+++ b/tests/test-chime-validation-retry.el
@@ -12,7 +12,7 @@
 ;;
 ;; Components tested:
 ;; - chime--validation-retry-count tracking
-;; - chime-validation-max-retries configuration
+;; - chime--validation-max-retries configuration
 ;; - chime-check validation retry logic
 ;; - chime--stop retry counter reset
 ;; - Message display behavior (waiting vs error)
@@ -24,7 +24,7 @@
 ;;; Setup and Teardown
 
 (defvar test-chime-validation-retry--original-max-retries nil
-  "Original value of chime-validation-max-retries for restoration.")
+  "Original value of chime--validation-max-retries for restoration.")
 
 (defvar test-chime-validation-retry--original-agenda-files nil
   "Original value of org-agenda-files for restoration.")
@@ -32,7 +32,7 @@
 (defun test-chime-validation-retry-setup ()
   "Set up test environment before each test."
   ;; Save original values
-  (setq test-chime-validation-retry--original-max-retries chime-validation-max-retries)
+  (setq test-chime-validation-retry--original-max-retries chime--validation-max-retries)
   (setq test-chime-validation-retry--original-agenda-files org-agenda-files)
 
   ;; Reset validation state
@@ -40,12 +40,12 @@
   (setq chime--validation-retry-count 0)
 
   ;; Set predictable defaults
-  (setq chime-validation-max-retries 3))
+  (setq chime--validation-max-retries 3))
 
 (defun test-chime-validation-retry-teardown ()
   "Clean up test environment after each test."
   ;; Restore original values
-  (setq chime-validation-max-retries test-chime-validation-retry--original-max-retries)
+  (setq chime--validation-max-retries test-chime-validation-retry--original-max-retries)
   (setq org-agenda-files test-chime-validation-retry--original-agenda-files)
 
   ;; Reset validation state
@@ -179,14 +179,14 @@ process events normally."
 (ert-deftest test-chime-validation-retry-boundary-max-retries-zero ()
   "Test max-retries=0 shows error immediately without retrying.
 
-When chime-validation-max-retries is set to 0, validation failures
+When chime--validation-max-retries is set to 0, validation failures
 should immediately show the full error message without any retry
 attempts."
   (test-chime-validation-retry-setup)
   (unwind-protect
       (progn
         ;; Set max retries to 0
-        (setq chime-validation-max-retries 0)
+        (setq chime--validation-max-retries 0)
 
         ;; Empty org-agenda-files
         (setq org-agenda-files nil)
@@ -222,7 +222,7 @@ show full error."
   (unwind-protect
       (progn
         ;; Set max retries to 1
-        (setq chime-validation-max-retries 1)
+        (setq chime--validation-max-retries 1)
 
         ;; Empty org-agenda-files
         (setq org-agenda-files nil)
@@ -261,7 +261,7 @@ The (retry_count + 1)th attempt should show the error message."
   (unwind-protect
       (progn
         ;; Default max retries = 3
-        (setq chime-validation-max-retries 3)
+        (setq chime--validation-max-retries 3)
         (setq org-agenda-files nil)
 
         (cl-letf (((symbol-function 'chime--fetch-and-process)
@@ -346,7 +346,7 @@ displayed with all error details in the *Messages* buffer."
   (test-chime-validation-retry-setup)
   (unwind-protect
       (progn
-        (setq chime-validation-max-retries 2)
+        (setq chime--validation-max-retries 2)
         (setq org-agenda-files nil)
 
         (cl-letf (((symbol-function 'chime--fetch-and-process)
@@ -380,7 +380,7 @@ validation should never be marked as done."
   (test-chime-validation-retry-setup)
   (unwind-protect
       (progn
-        (setq chime-validation-max-retries 3)
+        (setq chime--validation-max-retries 3)
         (setq org-agenda-files nil)
 
         (cl-letf (((symbol-function 'chime--fetch-and-process)
@@ -406,7 +406,7 @@ many retry attempts, ensuring no integer overflow issues."
   (test-chime-validation-retry-setup)
   (unwind-protect
       (progn
-        (setq chime-validation-max-retries 1000)
+        (setq chime--validation-max-retries 1000)
         (setq org-agenda-files nil)
 
         (cl-letf (((symbol-function 'chime--fetch-and-process)
diff --git a/tests/test-integration-chime-mode.el b/tests/test-integration-chime-mode.el
index cd1fec5..40436fb 100644
--- a/tests/test-integration-chime-mode.el
+++ b/tests/test-integration-chime-mode.el
@@ -105,7 +105,7 @@ in the tooltip, not go blank."
         (org-agenda-files nil)
         (chime--validation-done nil)
         (chime--validation-retry-count 0)
-        (chime-validation-max-retries 0))
+        (chime--validation-max-retries 0))
     (unwind-protect
         (progn
           (chime-mode 1)