fix(lint): replace stale hook-extension template with canonical version

[twistedmelonman]

What this fixes

.claude/hooks/extensions/example.sh.disabled was a stale copy of the fleet-wide hook-extension template, predating the shellcheck fixes already applied upstream. It was the only failing file in this repo and accounted for all 13 shellcheck findings — the sole reason standards-check failed.

The file is replaced verbatim with the fleet-canonical version (sha256 d3b8d301ace5…), the same content already merged into spokane-snow, dumbify, and personify.

What was wrong

Finding	Fix
SC2155 (x6)	local var=$(cmd) masks the command's exit status. Split into a bare local declaration followed by assignment.
Quoting / SC2312	The hardcoded-secret regexes used \x27 escapes inside single quotes, which bash does not interpret. Rewritten as double-quoted patterns containing literal quote characters.
grep lookahead	TODO(?! #[0-9]) is PCRE syntax that grep -E does not support, so the TODO check never matched as intended. Replaced with a match-then-exclude pipeline.
SC2329 (x5)	Every check function was unreachable because all calls in main() were commented out. Calls are now real, each gated behind an ENABLE_* variable defaulting to 0.

Behavior is unchanged. An unmodified copy of this file still runs no checks — the ENABLE_* gates all default to 0, replacing the old commented-out calls. The difference is that the functions are now reachable, so shellcheck can see them and a user enables a check by setting a variable rather than by editing out a comment.

Why it matters

This gives the repo its first-ever standards-check run. The caller stub landed in d4ce5f0 as a non-required status; with this fix the check is green and the repo becomes eligible to make it required.

Verification

The standards harness was run from a checkout outside $HOME, so shellcheck cannot walk up and pick up ~/.shellcheckrc (a fake HOME= does not prevent this — the checkout must physically live outside $HOME).

• Before the fix: exit 1 — 13 findings, all in this one file, shellcheck the only failing linter.
• After the fix: exit 0 — clean.

Because a silent pass and a skipped file look identical in the output, a deliberate fault was injected into this exact file and re-scanned: shellcheck flagged it by path, confirming the clean result reflects a real scan rather than a skipped file. The fault was then removed and the file re-verified byte-identical to canonical.

https://claude.ai/code/session_01XTyHGrxSHqhck86SvGDn7o

[claude]

All changes are confined to .claude/hooks/extensions/example.sh.disabled, a template file that runs no checks by default. The changes fix shellcheck findings (local var=$(cmd) two-line split), replace a non-POSIX negative lookahead in grep with a portable grep -v pipeline, and replace the commented-out check list with ENABLE_*=0 guards. No production code paths are affected.

VERDICT: PASS