feat(cli): kind-aware shared-collection reconcile + string-or-table manifest (§11.6 docs C4)

Make the declarative collection surface carry a `kind` so docs (and future
kinds) are declarable. Back-compatible: the shipped `collections = ["catalog"]`
form still means kv.

- manifest: `collections` entries are now `CollectionDecl` — an untagged enum of
  a bare string (kv shorthand) or a `{ name, kind }` table (kind ∈ kv/docs).
  `Manifest::collections()` normalizes to `(name, kind)` pairs; build_bundle
  emits `[{name, kind}]`. Still `[group]`-only. Unit test covers the
  string-or-table mix + app rejection.
- apply: `Bundle.collections: Vec<CollectionSpec>` ({name, kind=default "kv"});
  `CurrentState.collections: Vec<(name,kind)>` via list_all_for_owner;
  `diff_collections` keys each change by name with `detail = kind` and identity
  `(LOWER(name), kind)` (so a kv and a docs collection of the same name are
  distinct); reconcile reads the kind from `detail`; state_token folds
  `coll|{kind}|{name}`; validate_bundle rejects unknown kinds + dups by
  (name,kind); `collection_report`/CollectionInfo + `pic collections ls` gain a
  kind column.

Existing kv journeys + nearest-wins still green (the bare-string form normalizes
to kind=kv end to end).

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

crates/picloud-cli/src/client.rs

@@ -1352,6 +1352,8 @@ impl Client {
 #[derive(Debug, Deserialize)]
 pub struct CollectionInfoDto {
     pub name: String,
+    #[serde(default)]
+    pub kind: String,
 }
 
 // ---------- DTOs (CLI-local, wire-shape-matched) ----------