fix(desktop): npub identity controls across profile, agents, and workflows (#7489)

🤖
## Summary

Building on #7488's npub foundation, this PR finishes the identity
display change for the controls where you actually manage people and
keys: profile, settings, agent access, and workflows. Everywhere in
these surfaces, an identity key shows — and copies — as its canonical
npub (npub is the human-readable encoding of a Nostr public key: the
compact `npub1j57...fjmv` form where space is tight, the full npub where
the whole key matters), and accepts npub as input.

After this change:

- Profile panel: the public-key row and the managed-by / declared-owner
copies show the full npub. If a key can't be encoded, you see
"Unavailable" with no copy button — never a raw or partial key.
- Settings: the identity card shows and copies the npub. The
hosted-communities account identity derives from the bound key
(`pubkey_hex`) — the same authority as the mismatch gate and hosted
operations — so the display can never disagree with what the app acts
on; an unusable hex falls back to a neutral label instead of rendering
the unverified server npub. The connected claim and a community's
Connect action require that same usable bound key to match the local one
— with no usable binding the card cannot claim connected or start
Connect, while the community list, linking, and delete/rebind recovery
stay available.
- Hosted create/onboarding: the account and device identity rows in the
create flow and owner onboarding derive from the same authoritative
fields (bound key / local key), with the same neutral fallback;
readiness requires a usable bound key that matches the local one.
- Respond-to allowlist (controls who may respond to an agent): entries
can be typed or pasted as hex or npub; both spellings of the same key
are recognized as one entry and dedupe. Search results, chips, and
remove buttons use the compact npub.
- Workflow key fields: to/from keys display as npubs in the form and
save back as canonical hex. Templates like `{{trigger.author}}`, roles,
and free text pass through untouched; placeholders accept both
spellings.
- Recipient and agent dialogs: the verify popover is npub-only (the
raw-hex line is gone); denied-membership screens never show a raw key.
- The Rust-side truncated display name (used for native surfaces) shows
the same compact npub, so those surfaces match the web UI.

Internal representation is unchanged: keys are still stored, sent, and
matched as canonical 64-character hex — npub is a display and input
spelling, normalized to hex at the boundary, so existing data and
integrations keep working. Bound-key usability and comparison use one
normalized form (trimmed, lowercased, 64 hex characters; npub rejected),
so padded or mixed-case spellings of the same key match. Display names,
private keys, and event IDs are untouched.

## Details

- `respondToAllowlist` / `RespondToField`: npub entries normalize to
canonical hex; cross-form dedupe; compact npub in rows and chips;
direct-add accepts npub and stores canonical hex.
- `workflowFormTypes` / `WorkflowStepCard`: hex → npub for display, npub
→ canonical hex on save; templates, roles, and free text pass through in
both directions (roundtrip-tested).
- `UserProfilePanelFields`, `ProfileSettingsCard`,
`HostedCommunitiesSettingsCard`, `MembershipDenied`,
`SelectedRecipientChip`, `AddAgentToChannelDialog`: npub display and
copy; invalid keys → "Unavailable" with no copy; hosted identity rows
derive from the bound `pubkey_hex` (create/onboarding rows from the
bound and local keys), never the unverified server npub;
connected/readiness/Connect gates use the same usable-bound-key
predicate, and the settings Connect invocation callback re-checks it
before starting.
- `src-tauri/src/commands/identity.rs`: `truncated_display_name`
compacts to the first 8 + last 4 characters of the npub (above a 12-char
threshold), mirroring `truncateNpub`.
- e2e: profile key rows and clipboard polls assert npub forms and
raw-hex suppression; the display-screenshots spec pins the npub-only
popover; hosted specs drive the real settings card, create flow, and
onboarding rows through their real providers, and the unlinked/npub-only
identity cases assert no connected claim and no Connect action.

### Related issue

- Fixes: N/A. No separate issue; the related work is the stack below.
- Stack: builds on #7488 (shared npub foundation), now merged; this PR
is rebased onto main and stands on its own.

### Testing

At head `303c90ffa` (base: main `bfc38485`; 24 files, +1125/−146):

- Focused unit suites (respondToAllowlist, workflowFormTypes,
hostedCommunityApi bound-key helpers) green; mutation-checked — dropping
allowlist canonicalization fails the dedupe case, and dropping bound-key
normalization fails the npub-in-hex and padded same-key cases.
- Full desktop unit suite 6,477/6,477, `desktop-typecheck`,
`desktop-check` (formatting fixed narrowly with `biome check --write` on
the touched files only), and a fresh E2E build at the current head; the
add-community + hosted-communities-settings specs 18/18 and onboarding
integration 69/69 on a fresh dedicated port, with focused new-case runs
4+4 covering padded same-key (ready, Connect kept — no false rebind) and
npub-in-hex (neutral label, recovery, no Connect) across the settings
card, create flow, and first-community onboarding, plus the
unlinked-account settings regression asserting Connect cannot occur.
- `cargo fmt`/clippy (both feature sets) and `cargo test identity` (71
pass) passed at the earlier full-change head; since then, the only
production changes in this PR's delta are the hosted identity display
authority and its fail-closed bound-key gating/normalization above
(base-side fixes carry #7488's receipts) — every other change is
test-only.

### Task provenance

Buzz channel: `1f0e4a3d-7e01-4efe-bb16-843b357f85c9`

Task:
buzz://message?channel=1f0e4a3d-7e01-4efe-bb16-843b357f85c9&id=86b34eb4bd84a1472419e9af22636c011c0fe273e3c196f967d7a36996e149b6

---------

Signed-off-by: Logan Johnson <loganj@squareup.com>
Co-authored-by: Larry <627498bd4bd1f281a16431e3c6cce3b5c25b6692798c78672298aefbf2f8f8b5@buzz.block.builderlab.xyz>

scripts/check-pubkey-truncation-core.mjs

@@ -6,9 +6,11 @@ import path from "node:path";
  *
  * A truncated pubkey prefix is forgeable by vanity-grinding, so display
  * truncation must be consistent and centralized: the canonical
- * `truncatePubkey` in `shared/lib/pubkey.ts` (or the `<PubKey>` component,
- * which also offers full-key reveal + copy). Ad-hoc `pubkey.slice(0, N)`
- * display forms fragmented into five formats before this guard existed.
+ * `truncateNpub` (identity keys — compact npub) and `truncatePubkey`
+ * (generic hex identifiers such as event/blob IDs) in
+ * `shared/lib/pubkey.ts` (or the `<PubKey>` component, which also offers
+ * full-key reveal + copy). Ad-hoc `pubkey.slice(0, N)` display forms
+ * fragmented into five formats before this guard existed.
  *
  * It flags `.slice(` / `.substring(` / `.slice(0` template-truncations applied
  * to identifiers that look like a pubkey/npub, outside the canonical module.
@@ -97,7 +99,7 @@ export async function runPubkeyTruncationCheck({
   if (violations.length > 0) {
     console.error(
       `${label}: found ${violations.length} hand-rolled pubkey truncation(s).\n` +
-        `Use \`truncatePubkey\` from shared/lib/pubkey (or the <PubKey> component) instead.\n` +
+        `Use \`truncateNpub\` (identity) or \`truncatePubkey\` (event/blob IDs) from shared/lib/pubkey (or the <PubKey> component) instead.\n` +
         `Genuine non-display uses can be allowlisted in ${scriptPath}.\n`,
     );
     for (const violation of violations) {