fix(review): language-tagged suggestion fence for Gitea syntax highlighting

Gitea 1.26.x has no GitHub-style 'Apply suggestion' button — a ```suggestion
fence is just an unknown-language code block, so chroma does not highlight it
and there is no apply control. Switch inline_comment_body to wrap the suggested
fix in a fence tagged with the file's language (new _lang_for_path helper,
.java→java, .ts→typescript, .py→python, ...), so Gitea syntax-highlights the
code. No capability lost (there was never an apply button on this Gitea
version). Correct the docstrings/skills/README that wrongly claimed an
apply-button was rendered.

Co-Authored-By: Claude <noreply@anthropic.com>

.opencode/skills/review-methodology/SKILL.md

@@ -38,7 +38,8 @@ Each finding's `line` MUST be a line that exists in the POST-CHANGE version of
 Never anchor on a **removed** (`-`) line — it has no post-change line number.
 If you're unsure of the exact line, use the closest context line you CAN see in
 the diff. A misanchored finding becomes a summary bullet instead of an inline
-comment, so correct anchoring is what makes a ```suggestion apply-able in Gitea.
+comment, so correct anchoring is what gets a finding shown inline with its
+suggested-fix code block (language-highlighted) rather than demoted to a bullet.
 
 ## Honoring repo config