ad5ac0861d
## What was done
- **`the-matrix/js/session.js`** (new module): Full session mode UI lifecycle:
- Create session flow: amount presets → POST /api/sessions → deposit invoice step
- Deposit payment: stub simulate → 2s polling until state=active
- macaroon + sessionId stored in localStorage (`timmy_session_v1`)
- Request submission: intercepts input bar when session active → POST /api/sessions/:id/request
→ Timmy speech bubble shows result, balance updates in HUD
- Low-balance (< 50 sats): paused state, low-balance notice shown, topup quick-button
- Topup flow: preset amount → POST /api/sessions/:id/topup → topup invoice → stub pay → poll
- Restore from localStorage on page reload: validates session via GET, restores full UI state
- Session expiry / 401 macaroon rejection: clears storage, resets to unfunded state
- **`the-matrix/js/ui.js`**: Added `setSessionSendHandler(fn)` + `setInputBarSessionMode(active, placeholder)` exports; send() routes to session handler when active, falls back to WS visitor_message
- **`the-matrix/index.html`**:
- `#top-buttons` flex container: "⚡ SUBMIT JOB" (blue) + "⚡ FUND SESSION" (teal) side-by-side
- `#session-hud` balance line in HUD (green, hidden until session active)
- `#session-panel` left-side slide-in panel: fund / invoice / active / topup steps
- `.session-amount-btn` presets (200, 500, 1000, 2000, 5000 sats) with active state
- `#visitor-input.session-active` CSS: green border + 3s pulse keyframe animation
- `#low-balance-notice` strip above input bar with Top Up quick-button
- `.primary-green` / `.muted` panel button variants for session panel theme
- `#session-panel` inherits shared `.panel-btn`, `.invoice-box`, `.copy-btn` with green overrides
- **`the-matrix/js/main.js`**: Import + call `initSessionPanel()` in firstInit block
## Verification
- `npm run build` in the-matrix → clean build (0 errors)
- Full testkit: 27/27 PASS (all session tests 11–16, 22 still green)