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/package-lock.json

@@ -12,7 +12,6 @@
         "@tauri-apps/api": "^2",
         "@tauri-apps/plugin-dialog": "^2.7.0",
         "@tauri-apps/plugin-opener": "^2.5.3",
-        "@tauri-apps/plugin-store": "^2",
         "@xterm/addon-fit": "^0.10",
         "@xterm/addon-web-links": "^0.12.0",
         "@xterm/addon-webgl": "^0.18",
@@ -2010,15 +2009,6 @@
         "@tauri-apps/api": "^2.8.0"
       }
     },
-    "node_modules/@tauri-apps/plugin-store": {
-      "version": "2.4.2",
-      "resolved": "https://registry.npmjs.org/@tauri-apps/plugin-store/-/plugin-store-2.4.2.tgz",
-      "integrity": "sha512-0ClHS50Oq9HEvLPhNzTNFxbWVOqoAp3dRvtewQBeqfIQ0z5m3JRnOISIn2ZVPCrQC0MyGyhTS9DWhHjpigQE7A==",
-      "license": "MIT OR Apache-2.0",
-      "dependencies": {
-        "@tauri-apps/api": "^2.8.0"
-      }
-    },
     "node_modules/@testing-library/dom": {
       "version": "10.4.1",
       "resolved": "https://registry.npmjs.org/@testing-library/dom/-/dom-10.4.1.tgz",