[thekevinbot]

Speed-of-light test for dot-named files and directories (./.cache/**/*.md and two more). Test-only, no source change.

Stacked on #1356 (claude/1351-dot-dirs); base is that branch.

Measured on #1317 + #1356 combined (local merge, not pushed): native/dirsql seconds 0.555/0.194, 0.503/0.111, 0.658/0.211 (startup about 0.04s). Rows identical. All three pass.

On #1356 alone (no #1317 walker speed fixes) ./.cache/**/*.md misses the bar: native 0.733s, dirsql 1.020s less 0.040s startup. That is the main-walker slowness #1317 fixes, not a dot-handling cost. This PR's Python e2e therefore cannot go green until #1317 lands.

Fixes #1309

E2E Verification

• Ran e2e suites locally for every affected SDK
• Python SDK e2e: pending. The new file passes on Test one-level glob listings at speed of light #1317 + fix: a spelled dot component no longer opens dot directories above it #1356; the full suite is red on this base because glob_speed_depth_bound_test.py needs Test one-level glob listings at speed of light #1317
• TypeScript SDK e2e: pass
• Rust core e2e (if applicable): N/A
• packages/python/e2e-attestations/claude-1309-glob-speed.json receipt pending until Test one-level glob listings at speed of light #1317 lands; refresh after merging main
• packages/ts/e2e-attestations/claude-1309-glob-speed.json receipt written
• Command(s) run: uv run maturin develop --release, pytest tests/e2e/glob_speed_dotfiles_test.py (on Test one-level glob listings at speed of light #1317 + fix: a spelled dot component no longer opens dot directories above it #1356), just e2e-attest-ts
• Result summary: new Python file 3 passed (combined base); TS 18 passed