fix: assorted bug fixes for lists, sounds, interrupts, and permissions (#173)

## Summary

- **Markdown lists**: Explicitly set `list-style-type: disc` / `decimal` in the Markdown renderer — Tauri's WebView strips browser defaults, leaving bullets and numbers invisible.
- **Notification sounds**: Moved all per-task sounds (success, error, permission, task-start) from a global `characterState` subscription into the per-conversation `claude:state` event handler, so background tabs receive their sounds correctly and tab-switching never replays a sound that already fired. Closes #172
- **Draft text**: Persists `inputValue` per conversation tab so a half-typed prompt survives switching to another tab and back.
- **Interrupt messages**: Replaced vague "Process interrupted" / "Disconnected" strings with source-specific descriptions (keyboard shortcut, stop button, unexpected crash) so it's clear what actually happened.
- **Silent prompt loss**: When Claude Code exits whilst a prompt is in-flight, emits a visible error line telling the user their last prompt was not processed and to reconnect and retry.
- **Double disconnect**: Added an `intentional_stop` flag to `WslBridge` so that `stop()` / `interrupt()` — which kill the process themselves — suppress the duplicate "Disconnected unexpectedly" message that `handle_stdout`'s EOF path was also emitting.
- **Permission modal**: Fixed two cooperating reactivity bugs — `pendingPermissions` was mutated in-place (`.push()`), causing Svelte's derived-store chain to receive the same array reference and skip re-rendering; `PermissionModal.svelte` also used `$state()` (runes mode) where plain `let` is required for correct store-subscription reactivity.

## Test plan

- [ ] Unordered and ordered lists render with visible bullets and numbers in the chat terminal
- [ ] Completion sound plays once when a background tab finishes; switching back to that tab does not replay it
- [ ] Sounds for error, permission request, and task-start also play for background tabs and do not replay on tab switch
- [ ] Typing a prompt, switching tabs, and switching back restores the draft text
- [ ] Pressing Ctrl+C shows "keyboard shortcut (Ctrl+C)"; clicking the stop button shows "via stop button"
- [ ] If Claude exits mid-request, an error message appears prompting the user to resend
- [ ] Clicking stop or pressing Ctrl+C produces exactly one disconnect message (not two)
- [ ] When a tool requires permission, the permission modal appears and the user can approve or dismiss it

✨ This PR was created with help from Hikari~ 🌸

Reviewed-on: #173
Co-authored-by: Hikari <hikari@nhcarrigan.com>
Co-committed-by: Hikari <hikari@nhcarrigan.com>

src/lib/stores/conversations.test.ts

@@ -523,3 +523,41 @@ describe("pending retry message", () => {
     expect(pendingRetryMessage).toBeNull();
   });
 });
+
+describe("draft text persistence", () => {
+  it("initialises draft text as empty string", () => {
+    const conversation = { draftText: "" };
+    expect(conversation.draftText).toBe("");
+  });
+
+  it("stores draft text per conversation", () => {
+    const conversations = new Map([
+      ["conv-1", { draftText: "Hello world" }],
+      ["conv-2", { draftText: "" }],
+    ]);
+
+    expect(conversations.get("conv-1")?.draftText).toBe("Hello world");
+    expect(conversations.get("conv-2")?.draftText).toBe("");
+  });
+
+  it("updates draft text independently per conversation", () => {
+    const conversations = new Map([
+      ["conv-1", { draftText: "Draft A" }],
+      ["conv-2", { draftText: "Draft B" }],
+    ]);
+
+    const convA = conversations.get("conv-1");
+    if (convA) convA.draftText = "Updated A";
+
+    expect(conversations.get("conv-1")?.draftText).toBe("Updated A");
+    expect(conversations.get("conv-2")?.draftText).toBe("Draft B");
+  });
+
+  it("clears draft text after submission", () => {
+    const conversation = { draftText: "My prompt" };
+
+    conversation.draftText = "";
+
+    expect(conversation.draftText).toBe("");
+  });
+});