refactor(cj-org-text): extract Org-safe text sanitizers from calendar-sync

Phase 3 of utility-consolidation. Three sanitizers moved from calendar-sync.el into a new cj-org-text.el module so other consumers (web-clipper, AI conversation, mail-to-org capture) can compose Org content from external text without depending on calendar:

- `calendar-sync--sanitize-org-body' -> `cj/org-sanitize-body-text'
- `calendar-sync--sanitize-org-property-value' -> `cj/org-sanitize-property-value'
- `calendar-sync--sanitize-org-heading' -> `cj/org-sanitize-heading'

The helpers stay pure (string in, string out, nil-safe) and have no Org-mode dependency, so they work in batch and in tests without loading Org.

Migrate calendar-sync.el to use the new public names: drop the three local defuns, add `(require \='cj-org-text)', update the six call sites in `calendar-sync--make-event-entry'.

Move the existing 17-test file to `tests/test-cj-org-text-sanitize.el', rename test names to match the new helpers, add 1 nil-input test for `cj/org-sanitize-heading' that wasn't in the original file. Total: 18 Normal/Boundary tests across the three helpers.

1 files changed, 58 insertions, 0 deletions

diff --git a/modules/cj-org-text.el b/modules/cj-org-text.el
new file mode 100644
index 00000000..69224573
--- /dev/null
+++ b/modules/cj-org-text.el
@@ -0,0 +1,58 @@
+;;; cj-org-text.el --- Pure helpers for sanitizing external text into Org -*- lexical-binding: t; -*-
+
+;; Author: Craig Jennings <c@cjennings.net>
+
+;;; Commentary:
+
+;; Pure string helpers for safely composing Org-mode content from
+;; external text (calendar event bodies, web-clipped HTML, mail
+;; subject lines, AI conversation transcripts, etc.).
+;;
+;; The shared concern is that text from outside sources can contain
+;; characters that disturb Org structure if pasted verbatim:
+;;
+;; - leading `*' creates an unintended heading,
+;; - newlines inside a property value spawn extra drawer lines,
+;; - newlines inside a heading split it into two outline entries.
+;;
+;; These helpers neutralize each pattern with predictable, testable
+;; replacements.  They are pure (string in, string out, nil-safe) and
+;; have no Org-mode dependency, so they remain useful in batch and in
+;; tests without loading Org.
+
+;;; Code:
+
+(defun cj/org-sanitize-body-text (text)
+  "Sanitize TEXT for safe inclusion as Org body content.
+Replaces leading asterisks with dashes so external lines aren't
+parsed as Org headings.  Handles multiple levels (`**' becomes `--').
+Returns nil for nil input."
+  (when text
+    (replace-regexp-in-string
+     "^\\(\\*+\\) "
+     (lambda (match)
+       (concat (make-string (length (match-string 1 match)) ?-) " "))
+     text)))
+
+(defun cj/org-sanitize-property-value (text)
+  "Sanitize TEXT for safe inclusion as a single Org property value.
+Collapses whitespace and newlines into single spaces and trims, so the
+result fits on one line of an Org property drawer.  Returns nil for
+nil input."
+  (when text
+    (string-trim
+     (replace-regexp-in-string
+      "[[:space:]\n\r]+"
+      " "
+      text))))
+
+(defun cj/org-sanitize-heading (text)
+  "Sanitize TEXT for safe inclusion as a single Org heading title.
+Composes `cj/org-sanitize-body-text' (neutralizes leading stars) and
+`cj/org-sanitize-property-value' (flattens to a single line).  Returns
+nil for nil input."
+  (cj/org-sanitize-property-value
+   (cj/org-sanitize-body-text text)))
+
+(provide 'cj-org-text)
+;;; cj-org-text.el ends here