refactor: rename debug-wttrin-* commands to wttrin-debug-* with obsolete aliases

The four interactive commands in `wttrin-debug.el` used `debug-wttrin-` as their prefix instead of the package's `wttrin-debug-` prefix. package-lint flags this as a convention violation, and it makes M-x discovery slightly less consistent for users.

Renamed:
- `debug-wttrin-show-raw`   -> `wttrin-debug-show-raw`
- `debug-wttrin-enable`     -> `wttrin-debug-enable`
- `debug-wttrin-disable`    -> `wttrin-debug-disable`
- `debug-wttrin-mode-line`  -> `wttrin-debug-mode-line`

The old names stay available as `define-obsolete-function-alias` entries marked since 0.4.0, so anyone with a keybinding or `(call-interactively 'debug-wttrin-enable)` in their config keeps working. The byte-compiler will emit an obsolescence warning to nudge migration. Aliases will be removed in a future release.

Internal caller `wttrin--debug-mode-line-info` now invokes the new name. Test files renamed to match (`test-debug-wttrin-*.el` -> `test-wttrin-debug-*.el`); inside each, ert-deftest names and function calls were updated.

Added `tests/test-wttrin-debug-aliases.el` to verify each old name resolves via `indirect-function` to the new name and carries `byte-obsolete-info` with the expected target and "0.4.0" version.

1 files changed, 79 insertions, 0 deletions

diff --git a/tests/test-wttrin-debug-mode-line.el b/tests/test-wttrin-debug-mode-line.el
new file mode 100644
index 0000000..b9e135b
--- /dev/null
+++ b/tests/test-wttrin-debug-mode-line.el
@@ -0,0 +1,79 @@
+;;; test-wttrin-debug-mode-line.el --- Tests for wttrin-debug-mode-line -*- lexical-binding: t; -*-
+
+;; Copyright (C) 2025-2026 Craig Jennings
+
+;;; Commentary:
+
+;; Unit tests for wttrin-debug-mode-line.  This function is a UI-heavy
+;; diagnostic dump, so testing focuses on the two top-level branches:
+;; - When *wttr.in* is missing, no diagnostic buffer is produced.
+;; - When *wttr.in* exists, the diagnostic buffer is created and contains
+;;   the expected section labels.
+
+;;; Code:
+
+(require 'ert)
+(require 'wttrin)
+(require 'testutil-wttrin)
+
+(require 'wttrin-debug
+         (expand-file-name "wttrin-debug.el"
+                           (file-name-directory (locate-library "wttrin"))))
+
+;;; Setup and Teardown
+
+(defun test-wttrin-debug-mode-line-setup ()
+  "Setup for wttrin-debug-mode-line tests."
+  (when (get-buffer "*wttr.in*")
+    (kill-buffer "*wttr.in*"))
+  (when (get-buffer "*wttrin-mode-debug*")
+    (kill-buffer "*wttrin-mode-debug*")))
+
+(defun test-wttrin-debug-mode-line-teardown ()
+  "Teardown for wttrin-debug-mode-line tests."
+  (when (get-buffer "*wttr.in*")
+    (kill-buffer "*wttr.in*"))
+  (when (get-buffer "*wttrin-mode-debug*")
+    (kill-buffer "*wttrin-mode-debug*")))
+
+;;; Normal Cases
+
+(ert-deftest test-wttrin-debug-mode-line-normal-no-buffer-skips-diagnostic-buffer ()
+  "When the *wttr.in* buffer is absent, no diagnostic buffer is created."
+  (test-wttrin-debug-mode-line-setup)
+  (unwind-protect
+      (progn
+        (wttrin-debug-mode-line)
+        (should-not (get-buffer "*wttrin-mode-debug*")))
+    (test-wttrin-debug-mode-line-teardown)))
+
+(ert-deftest test-wttrin-debug-mode-line-normal-buffer-exists-creates-diagnostic-buffer ()
+  "When the *wttr.in* buffer exists, the diagnostic buffer is created."
+  (test-wttrin-debug-mode-line-setup)
+  (unwind-protect
+      (progn
+        (with-current-buffer (get-buffer-create "*wttr.in*")
+          (wttrin-mode))
+        (wttrin-debug-mode-line)
+        (should (get-buffer "*wttrin-mode-debug*")))
+    (test-wttrin-debug-mode-line-teardown)))
+
+(ert-deftest test-wttrin-debug-mode-line-normal-diagnostic-buffer-contains-section-labels ()
+  "Diagnostic buffer contains the expected section labels."
+  (test-wttrin-debug-mode-line-setup)
+  (unwind-protect
+      (progn
+        (with-current-buffer (get-buffer-create "*wttr.in*")
+          (wttrin-mode))
+        (wttrin-debug-mode-line)
+        (with-current-buffer "*wttrin-mode-debug*"
+          (let ((contents (buffer-string)))
+            (should (string-match-p "Wttrin Mode-Line Debug Info" contents))
+            (should (string-match-p "Buffer:" contents))
+            (should (string-match-p "Major mode:" contents))
+            (should (string-match-p "mode-name variable:" contents))
+            (should (string-match-p "mode-line-format first 5 elements:" contents)))))
+    (test-wttrin-debug-mode-line-teardown)))
+
+(provide 'test-wttrin-debug-mode-line)
+;;; test-wttrin-debug-mode-line.el ends here