docs: fix PLAN.md catalog and MDS023 readability in plan/2606240212

PLAN.md catalog was out of date (MDS019): regenerated to include the
three new plan files added in the rename-dedup work.

plan/2606240212: paragraph at line 26 exceeded the readability index
(MDS023). Rewrote to use shorter sentences without changing meaning.

Author: claude

PLAN.md

@@ -227,5 +227,5 @@ footer: |
 | 2606240211 | ✅     | sonnet | [Add dedicated unit tests for locate.go helpers](plan/2606240211_arch-fix-locate-helper-tests.md)                                       |
 | 2606240212 | 🔲     | sonnet | [Add dedicated unit tests for lsp/rename.go helpers](plan/2606240212_arch-fix-lsp-rename-helper-tests.md)                               |
 | 2606240213 | 🔲     | sonnet | [Add dedicated unit tests for export.go helpers and two small rename helpers](plan/2606240213_arch-fix-export-helper-tests.md)          |
-| 2606240214 | 🔲     | sonnet | [Remove duplicated helpers between lsp/rename.go and rename/rename.go](plan/2606240214_arch-fix-rename-dedup.md)                        |
+| 2606240214 | ✅     | sonnet | [Remove duplicated helpers between lsp/rename.go and rename/rename.go](plan/2606240214_arch-fix-rename-dedup.md)                        |
 <?/catalog?>

plan/2606240212_arch-fix-lsp-rename-helper-tests.md

@@ -23,14 +23,11 @@ Go arch doc §"Tests" requires every production function
 to have a dedicated test by name. The 2026-06-24 audit
 (range: 1599c9f..09f22d3) flagged this file.
 
-`atxHeadingTextByteRange` already has a test. The
-three trivial pass-through methods on the workspace
-adapter carry exemption comments. `refDefBracketBytes`
-and `normalizedLabel` were removed from lsp/rename.go
-in PR claude/youthful-knuth-hsz74x (exported as
-`rename.RefDefBracketBytes` and `rename.NormalizedLabel`
-with tests in `internal/rename`). The 13 helpers
-below need dedicated tests:
+`atxHeadingTextByteRange` already has a test.
+Three pass-through adapter methods carry exemption
+comments. Two helpers were removed from this file.
+Both now live in `internal/rename` with tests.
+The 13 helpers below need tests:
 
 - `isValidRefDefLine`
 - `headingPrepareRange`