UI half of the profile feature. Mirrors the previous three commits
so the user can browse and edit profiles.
* `<Avatar did cid name size>` — reusable avatar component.
Falls back to an initial-letter (or "?" when name is empty) circle
when `cid` is null. Resolves the blob through the standard PDS
fetch path so it works for any author whose PDS the client can
reach.
* `<UserProfileView handle on_thread_click current_user_did>` —
public profile page. Fetches `GET /api/profile/<handle>` on
mount, renders the avatar / display name / bio / counts /
posts. The "edit profile" button is gated on
`current_user_did === profile.did` so a user browsing
someone else's profile can't issue an unintended `setMyProfile`
against their own DID.
* `PostCard` now renders an inline `<Avatar>` + clickable handle
button that calls a new `on_handle_click` prop. The clickable
area replaces the previous dead `<a href>` (Tauri webviews
have no router).
* `App.svelte` adds an `openUserProfile(handle)` handler that
sets `selectedHandle` + `view = "user"` and mounts
`<UserProfileView>`.
* New Tauri commands `profile_get_record` / `profile_set` in
`lib.rs` + matching client helpers `getMyProfile` /
`setMyProfile` in `client.ts`. The set command sends camelCase
field names; the PDS endpoint (previous commit) round-trips them
through `#[serde(rename_all = "camelCase")]`.
* Empty-state UX for users with no profile yet (new account, or a
third-party-PDS author whose profile the AppView hasn't indexed
yet): both the current-user "profile" view and the public
"user" view render a hint ("// no profile yet — click 'edit
profile' to set one up." / "// no profile yet.") instead of a
blank bio box.
* NavRail / NavRailHarness `View` union extended with "user"
so the navigation prop type accepts the new view.
tomdebone
ffee5c6685