chore(lint): bring .tsx files into the eslint, lefthook, and jscpd lanes

.tsx sources and specs were invisible to every lint surface: the eslint
flat-config globs, the lefthook staged-file glob, and the jscpd clone
scan all matched *.ts only. Widen the five eslint file groups (source,
test, client-test, sonar, formatting), the pre-commit glob, and the
jscpd format/pattern to cover .tsx.

Existing .tsx files predate these lanes; follow-up commits on this PR
clear the backlog they surface.

.jscpd.json

@@ -2,8 +2,8 @@
   "minTokens": 60,
   "minLines": 6,
   "mode": "mild",
-  "format": ["typescript"],
-  "pattern": "**/*.ts",
+  "format": ["typescript", "tsx"],
+  "pattern": "**/*.{ts,tsx}",
   "ignore": ["**/tests/**", "**/tsdown.config.ts"],
   "ignorePattern": [
     "(?s)/\\* jscpd:ignore-start \\*/.*?/\\* jscpd:ignore-end \\*/"