fix: surface approval prompt in UI instead of getting stuck in Thinking (#187)

* fix: surface approval prompt in UI instead of getting stuck in Thinking

When a dangerous command was detected during streaming, the approval system
would call submit_pending() but no SSE 'approval' event would be emitted to
the frontend. The agent thread either blocked indefinitely (gateway path) or
returned an approval_required status the UI never saw (EXEC_ASK path). Either
way the chat UI stayed stuck in 'Thinking...' with no prompt shown.

Root cause: streaming.py used HERMES_EXEC_ASK=1 but never registered a
register_gateway_notify() callback. Without it, check_all_command_guards()
fell back to the legacy polling path (submit_pending only), which relies on
on_tool() polling -- but on_tool() fires *before* the tool runs, so by the
time the terminal tool detected the dangerous command and called submit_pending,
the approval event had already missed its window.

Fix (streaming.py):
- Register a gateway-style notify_cb via register_gateway_notify() before the
  agent runs. The callback calls put('approval', ...) to emit the SSE event
  the moment a dangerous command is detected, regardless of on_tool() timing.
- Unregister via unregister_gateway_notify() in the finally block to unblock
  any threads still waiting if the stream ends or is cancelled mid-approval.
- Keep the on_tool() fallback poll for older approval module versions.

Fix (routes.py):
- Import and call resolve_gateway_approval() in _handle_approval_respond().
  This unblocks the agent thread parked in entry.event.wait() when the user
  clicks Allow or Deny in the UI. Without this call the thread would block
  until the 5-minute gateway timeout.

Tests (tests/test_approval_unblock.py):
- 16 new tests covering: resolve_gateway_approval() event signalling, deny/
  session/once choices, resolve_all, notify_cb registration/firing/cleanup,
  unregister signals blocked entries, full end-to-end streaming simulation,
  module symbol exports, and HTTP endpoint regressions.

515 tests pass (499 existing + 16 new).

* feat: full approval UI — i18n buttons, keyboard shortcut, loading state, scoping fix

---------

Co-authored-by: Nathan Esquenazi <nesquena@gmail.com>

static/style.css

@@ -164,19 +164,27 @@
   /* ── Approval card ── */
   .approval-card{display:none;max-width:780px;margin:0 auto 0;padding:0 20px 12px;}
   .approval-card.visible{display:block;}
-  .approval-inner{background:var(--surface);backdrop-filter:blur(8px);border:1px solid rgba(233,69,96,0.35);border-radius:14px;padding:14px 16px;}
+  .approval-inner{background:var(--surface);backdrop-filter:blur(8px);border:1px solid rgba(233,69,96,0.35);border-radius:14px;padding:16px 18px;}
   .approval-header{display:flex;align-items:center;gap:8px;margin-bottom:10px;font-size:13px;font-weight:600;color:#e94560;}
-  .approval-desc{font-size:12px;color:var(--muted);margin-bottom:8px;}
-  .approval-cmd{background:var(--code-bg);border:1px solid var(--border);border-radius:8px;padding:8px 12px;font-family:"SF Mono",ui-monospace,monospace;font-size:12px;color:var(--pre-text);white-space:pre-wrap;word-break:break-all;margin-bottom:12px;max-height:120px;overflow-y:auto;}
-  .approval-btns{display:flex;gap:8px;flex-wrap:wrap;}
-  .approval-btn{padding:6px 14px;border-radius:8px;font-size:12px;font-weight:600;border:1px solid var(--border2);background:var(--hover-bg);color:var(--text);cursor:pointer;transition:all .15s;}
-  .approval-btn:hover{background:rgba(255,255,255,0.12);}
-  .approval-btn.once{border-color:rgba(124,185,255,0.5);color:var(--blue);}
-  .approval-btn.once:hover{background:rgba(124,185,255,0.15);}
-  .approval-btn.session{border-color:rgba(124,185,255,0.3);color:var(--blue);}
+  .approval-desc{font-size:12px;color:var(--muted);margin-bottom:8px;line-height:1.5;}
+  .approval-cmd{background:var(--code-bg);border:1px solid var(--border);border-radius:8px;padding:8px 12px;font-family:"SF Mono",ui-monospace,monospace;font-size:12px;color:var(--pre-text);white-space:pre-wrap;word-break:break-all;margin-bottom:14px;max-height:120px;overflow-y:auto;}
+  .approval-btns{display:flex;gap:8px;flex-wrap:wrap;align-items:center;}
+  .approval-btn{display:inline-flex;align-items:center;gap:6px;padding:7px 15px;border-radius:8px;font-size:12px;font-weight:600;border:1px solid var(--border2);background:var(--hover-bg);color:var(--text);cursor:pointer;transition:all .15s;white-space:nowrap;}
+  .approval-btn:hover{background:rgba(255,255,255,0.12);transform:translateY(-1px);box-shadow:0 2px 8px rgba(0,0,0,0.2);}
+  .approval-btn:active{transform:translateY(0);box-shadow:none;}
+  .approval-btn:disabled{opacity:.5;cursor:not-allowed;transform:none;}
+  .approval-btn-icon{font-size:13px;line-height:1;}
+  .approval-btn-label{line-height:1;}
+  .approval-kbd{display:inline-flex;align-items:center;justify-content:center;padding:1px 5px;border-radius:4px;font-size:10px;font-family:inherit;background:rgba(255,255,255,.08);border:1px solid rgba(255,255,255,.15);color:var(--muted);line-height:1.4;margin-left:2px;}
+  .approval-btn.once{border-color:rgba(124,185,255,0.6);color:var(--blue);background:rgba(124,185,255,0.08);}
+  .approval-btn.once:hover{background:rgba(124,185,255,0.18);border-color:rgba(124,185,255,0.8);}
+  .approval-btn.session{border-color:rgba(124,185,255,0.35);color:var(--blue);}
+  .approval-btn.session:hover{background:rgba(124,185,255,0.12);border-color:rgba(124,185,255,0.55);}
   .approval-btn.always{border-color:rgba(201,168,76,0.5);color:var(--gold);}
+  .approval-btn.always:hover{background:rgba(201,168,76,0.12);border-color:rgba(201,168,76,0.7);}
   .approval-btn.deny{border-color:rgba(233,69,96,0.5);color:var(--accent);}
-  .approval-btn.deny:hover{background:rgba(233,69,96,0.12);}
+  .approval-btn.deny:hover{background:rgba(233,69,96,0.12);border-color:rgba(233,69,96,0.7);}
+  .approval-btn.loading{opacity:.7;cursor:wait;}
   /* Sidebar navigation tabs */
   .sidebar-nav{display:flex;border-bottom:1px solid var(--border);flex-shrink:0;padding:6px 8px 0;gap:2px;}
   .nav-tab{flex:1;padding:10px 4px 8px;font-size:20px;text-align:center;cursor:pointer;color:var(--muted);border:none;background:none;transition:color .15s;border-bottom:2px solid transparent;white-space:nowrap;overflow:hidden;position:relative;}
@@ -462,6 +470,7 @@
     .approval-card{padding:0 10px 8px;}
     .approval-btns{gap:6px;}
     .approval-btn{padding:8px 12px;font-size:12px;min-height:44px;}
+    .approval-kbd{display:none;}
     /* Tool cards */
     .tool-card{margin-left:0!important;font-size:12px;}
     /* Settings modal */