polish(permissions): per-permission emoji glyphs + test-coupling cleanup
Two more polishes on the web-permissions surface:
1. **Per-permission emoji glyphs** — visual scan helper rendered next
to the label in BOTH the page-host prompt and each Settings →
Permissions row. Helps the user tell "this is geolocation" 📍
from "this is camera/mic" 🎤 at a glance instead of reading the
words. Same glyph set used in both places (defined as
`PERMISSION_GLYPHS` in app/page/page.js and mirrored in
app/settings/settings.js — keep in sync). Glyphs:
📍 geolocation 🎤 media 🎹 midi/midiSysex
📺 display-capture 🔔 notifications 📋 clipboard-*
🖱️ pointerLock ⤢ fullscreen 🔗 openExternal
Falls back to 🔒 for unknown permissions.
2. **Test-coupling cleanup** — added a `test.beforeEach` to the
Permission Prompt suite that calls
`app.permissions.forgetAll()` on bgWindow before every test.
Previously each test that needed clean state sprinkled its own
reset; now the hygiene lives in one place and individual tests
don't accidentally depend on whether a prior test happened to
persist a decision. Removed the per-test resets that were added
in the prior commit.
Tests:
* permission-prompt 6/6 — same coverage, cleaner setup.
* permissions-settings 5/5 — unchanged, glyph addition is
cosmetic (label text gains a leading emoji).
No backend changes. Renderer + test polish only.