[P.1] chore(hooks): add 800-line file size pre-commit gate

[h4yfans]

Summary

Adds .githooks/pre-commit that blocks commits introducing source files over 800 lines. Keeps module boundaries honest: split files before they grow unreviewable.

• Scope: apps/** and packages/** source only
• Excluded: tests (*.test.*, *.spec.*, tests/**), *.d.ts, generated IPC map, build output, node_modules, .worktrees, .claude
• Limit: MAX_LINES=800 (lives in the hook itself)
• Activation: core.hooksPath=.githooks is set by the existing root prepare script, so pnpm install picks it up automatically

Hook source

` ``sh
#!/usr/bin/env bash

Reject commits that introduce or modify any source file exceeding MAX_LINES.

Keeps module boundaries honest — split files before they become unreviewable.

set -eu

MAX_LINES=800

excluded() {
case "$1" in
node_modules/|/node_modules/) return 0 ;;
.worktrees/|/.worktrees/) return 0 ;;
.claude/) return 0 ;;
dist/|/dist/) return 0 ;;
out/|/out/) return 0 ;;
coverage/|/coverage/) return 0 ;;
tests/|/tests/*) return 0 ;;
.test.ts|.test.tsx) return 0 ;;
.spec.ts|.spec.tsx) return 0 ;;
.d.ts) return 0 ;;
generated-ipc-invoke-map.ts) return 0 ;;
esac
case "$1" in
apps/|packages/) return 1 ;;
/) return 0 ;;
*) return 1 ;;
esac
}

offender_files=()
offender_lines=()

while IFS= read -r file; do
[ -z "$file" ] && continue
[ -f "$file" ] || continue
if excluded "$file"; then
continue
fi
lines=$(wc -l < "$file" | tr -d ' ')
if [ "$lines" -gt "$MAX_LINES" ]; then
offender_files+=("$file")
offender_lines+=("$lines")
fi
done < <(git diff --cached --name-only --diff-filter=ACMR)

count=${#offender_files[@]}

if [ "$count" -gt 0 ]; then
printf '\n\033[31mpre-commit: %d file(s) exceed %d-line limit:\033[0m\n\n' "$count" "$MAX_LINES" >&2
printf ' %-70s %s\n' "FILE" "LINES" >&2
printf ' %-70s %s\n' "----" "-----" >&2
for i in "${!offender_files[@]}"; do
printf ' %-70s %s\n' "${offender_files[$i]}" "${offender_lines[$i]}" >&2
done
printf '\nSplit these files into smaller modules before committing.\n' >&2
printf 'Limit lives in .githooks/pre-commit (MAX_LINES).\n\n' >&2
exit 1
fi

exit 0
` ``

Fail-case transcript (801-line file rejected)

` ``
$ awk 'BEGIN{for(i=0;i<801;i++)print "// line " i}' > apps/desktop/src/_throwaway.ts
$ wc -l apps/desktop/src/_throwaway.ts
801 apps/desktop/src/_throwaway.ts
$ git add apps/desktop/src/_throwaway.ts
$ git commit -m "test-oversized"

pre-commit: 1 file(s) exceed 800-line limit:

FILE LINES

---

apps/desktop/src/_throwaway.ts 801

Split these files into smaller modules before committing.
Limit lives in .githooks/pre-commit (MAX_LINES).
` ``

Hook exits non-zero, commit aborted.

Pass-case transcript (799-line file accepted)

`` \$ awk 'BEGIN{for(i=0;i<799;i++)print "// line " i}' > apps/desktop/src/_okay.ts \$ wc -l apps/desktop/src/_okay.ts 799 apps/desktop/src/_okay.ts \$ git add apps/desktop/src/_okay.ts \$ git commit -m "test-ok" [debt/P.1-file-size-precommit 7d4f5726] test-ok 1 file changed, 799 insertions(+) create mode 100644 apps/desktop/src/_okay.ts \$ git reset --hard HEAD~1 HEAD is now at 77ec9ea3 chore(hooks): add 800-line file size pre-commit gate ``

Test plan

• Hook file executable (-rwxr-xr-x)
• core.hooksPath resolves to .githooks (set by root prepare script)
• 801-line source file commit rejected with clear error
• 799-line source file commit accepted
• pnpm lint passes
• pnpm --filter @memry/desktop typecheck:node passes
• pnpm --filter @memry/desktop typecheck:web passes
• pnpm typecheck:packages passes
• pnpm test passes (ignored known calendar-page.test.tsx:258 "Due draft" flake)