Reconcile the frontend with the round-1 backend contracts

Five backend branches merged and the TypeScript still compiled, because
none of this is a type error: a field that arrives `undefined`, a variant
nothing emits any more, a prompt whose loop never closes. Six things.

**Orphaned volumes are destructive now, not safe.** `ReclaimTarget::
OrphanVolume` is gone from Rust; the object is a `DestructiveTarget::
OrphanVolume { name, project_id }` confirmed against the *volume's* name,
there being no project to name. The TS union still listed it under
`ReclaimTarget`, and — worse — `DiskProjectTable` keys destructive items
off `project_id`, which an orphan's never matches. So the item existed in
the plan and appeared nowhere on screen. `DiskSettings` now splits the
plan's destructive list and gives orphans their own section with a
per-volume `TypedConfirmModal`. The copy says what a
`triple-c-claude-config-*` volume actually is — a Claude login
credential, every plugin and skill, every transcript that project had —
and keeps the sentence explaining that "no matching project" is a lookup
against the project list and is never inferred from a project being
stopped or having no image, which is the inference that once flagged two
live projects.

`TypedConfirmModal` grew a `subject` prop: asking a user for "the exact
project name" of a volume that has no project is asking for a string that
does not exist.

**Snapshot and Total reconcile.** `ProjectDiskRow.snapshot_attributed_bytes`
is the single figure `snapshot_attribution()` exists to produce. The
column rendered `snapshot_above_base_bytes` and fell back to `—` while
the Total was `size - shared` regardless — and in that branch `size -
shared` is the whole 4.7 GB base image, charged per project and then
added again as a base-image row. One field, one rule. The one branch
where the figure *is* the whole image says so rather than passing itself
off as a share.

**The overwrite loop closes.** Traced end to end: a `FILE_EXISTS:`
refusal raises the prompt, Replace re-invokes with `overwrite: true`,
Skip advances, "…all" answers the rest without asking, and picker and
host-drop both reach `uploadFileToContainer` through `uploadPaths`. Two
gaps: a second batch's `askOverwrite` overwrote the first's resolver,
leaving that batch awaiting an answer no dialog could produce; and the
backend's written refusals — a hidden host folder, a path outside the
write roots — were passed as a toast `detail`, which `ToastHost` renders
as collapsed monospace behind a "Details" button, so the only sentence
that explained anything was the part nobody saw. `readableRefusal`
promotes it to the headline when a batch failed the same way.

**The browser pane's sandbox is pinned.** `allow-same-origin` must stay
(the proxy's gate reads `Origin`/`Referer`, and an opaque origin sends
`null`); every top-navigation grant and `allow-popups-to-escape-sandbox`
must stay absent, and the test names the offending token rather than
printing a set diff.

**`@tauri-apps/plugin-store` is gone** from `package.json` — its
capability grants were removed as a host-file-write primitive and nothing
in `app/src` imports it. The lockfile was updated with
`--package-lock-only`, deliberately: `node_modules` is a symlink shared
with other worktrees and a real install would have pulled it out from
under them.

Nothing under `src-tauri/` is touched. 663 frontend tests pass (was 635),
`tsc --noEmit` clean, `npm run build` green, `cargo test` 446 unchanged.

Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01GBq2rGum6GX7xXgsas1fDc

app/src/components/ui/TypedConfirmModal.test.tsx

@@ -71,6 +71,16 @@ describe("TypedConfirmModal", () => {
     expect(screen.getByRole("status")).toHaveTextContent("Name matches.");
   });
 
+  it("names what it is waiting for, when that is not a project", () => {
+    // An orphaned volume has no project — its id matches nothing in the store,
+    // which is the definition of the variant — so the gate takes the volume's
+    // own name and must not ask for a string that does not exist.
+    renderModal({ expected: "triple-c-claude-config-gone", subject: "volume name" });
+    expect(screen.getByRole("status")).toHaveTextContent(
+      "Waiting for the exact volume name.",
+    );
+  });
+
   it("spells out what is lost, from the caller's copy", () => {
     renderModal();
     expect(screen.getByText("Everything goes.")).toBeInTheDocument();

app/src/components/ui/TypedConfirmModal.tsx

@@ -7,6 +7,16 @@ interface Props {
   title: string;
   /** What must be typed, verbatim, before the confirm button enables. */
   expected: string;
+  /**
+   * What `expected` *is*, for the waiting message — "project name" unless the
+   * caller says otherwise.
+   *
+   * An orphaned volume has no project by definition, so its gate takes the
+   * volume's own name (that is what `disk.rs`'s `destroy` compares against),
+   * and telling that user we are "waiting for the exact project name" would be
+   * asking for a string that does not exist.
+   */
+  subject?: string;
   /** The verb on the confirm button. Repeat the action — never "OK". */
   confirmLabel: string;
   /** What is about to be lost, in full. */
@@ -46,6 +56,7 @@ interface Props {
 export default function TypedConfirmModal({
   title,
   expected,
+  subject = "project name",
   confirmLabel,
   children,
   onConfirm,
@@ -115,7 +126,7 @@ export default function TypedConfirmModal({
               // Not disabled content — the gate is live and waiting on the
               // user. `--text-disabled` is ~4.1:1 and fails AA at 12px.
               <span className="text-[var(--text-secondary)]">
-                Waiting for the exact project name.
+                Waiting for the exact {subject}.
               </span>
             )}
           </p>