feat(cli)!: v0.10 reliability, agent-UX, and command-surface hardening

A hardening + finalization pass over the agent-first CLI: correctness fixes,
richer machine-readable signals, flag/naming consistency, and a symmetric
config surface. Pre-1.0, so it includes breaking renames.

Correctness:
- agent update: resolve/validate --model/--rerank-model (was storing a bogus
  name verbatim, corrupting config.model_id).
- doctor: honor WEKNORA_HOST / WEKNORA_API_KEY (headless path no longer reports
  "no host configured").
- session ask / MCP session_ask: text answer was empty on non-TTY — the agent
  stream sets Done=true on an intermediate agent_query frame before the answer,
  and AgentAccumulator treated the first Done as terminal. Terminate on the
  `complete` event (new sdk.AgentResponseTypeComplete), not a per-frame Done.
- batch exit codes: any per-item failure collapses to operation.failed (exit 1),
  including `doc upload --recursive` partial failures — a permanent per-file
  failure (e.g. a duplicate) no longer surfaces as a retryable exit 7 an agent
  would loop on; per-item typed errors stay in the envelope.

Agent-first signals & discovery:
- error.exit_code in the envelope (type + exit_code disambiguate the
  input.invalid_argument exit-2-vs-5 split in one JSON read).
- meta.hint on empty content search and on draft doc create; doc wait fails fast
  on a never-parsing draft instead of hanging to --timeout.
- retrieval-readiness is visible in the natural flow: kb status / kb check emit
  retrieval_ready, and kb create hints the fix when no embedding model is bound
  — an unconfigured KB no longer looks silently healthy.
- schema contract completeness: every leaf declares output + >=1 example
  (drift-guarded); output strings match the meta actually emitted; chunk list
  and search docs now emit meta.total_count (both previously dropped it).
- schema tolerates a quoted multi-word command label; zero-state auth — and
  `link` with no profile — point at profile setup / the headless WEKNORA_KB_ID
  path instead of looping on `auth login`.
- id-addressed reads tolerate a redundant --kb (doc view/wait, chunk list/view
  accept and ignore it, declared in schema) so a carried-over --kb doesn't
  exit 2; streaming commands warn that --jq does not apply to an NDJSON stream.
- keep JSON-always as the default; --jq hints spell out the .data path.

Consistency & gating:
- doc create: drop the deprecated --name alias (--title only; pre-1.0 break).
- chunk list --limit aligned to 1..10000; model list --limit/-L with
  has_more/total_count; api write-gates -X PUT/PATCH (exit 10); skills install
  expands a leading ~.
- docs corrected: search docs / doc list --keyword help is case-insensitive
  (server does LOWER LIKE); AGENTS.md risk-action list (no phantom kb.init; add
  model.update / kb.config.set) and batch example (failed item carries `error`);
  session resume --message id comes from `message list`, not the stream.
- auth/profile ergonomics: env credentials are now first-class — `auth token`
  prints the active WEKNORA_API_KEY / WEKNORA_TOKEN, and auth login/logout/refresh
  give an env-aware message instead of looping on "run auth login". `auth logout`
  clears credentials but keeps the profile registered (host preserved for
  re-login); deleting a profile is `profile remove`'s job (clean logout/remove
  separation, matching gh / lark).

Config surface (symmetric read/write, in-place model edits):
- kb config now returns a secret-free KBModelConfigView (was {}); `kb config`
  reads, new `kb config set` writes; `kb init` removed (misnomer).
- kb create --chat-model: retrieval-ready in one step.
- model update: edit a model in place (id preserved, references survive) —
  rotate --api-key-stdin, change base-url / display-name / etc.
- session continue-stream renamed to session resume.

Docs: AGENTS.md is the single wire-contract source; CHANGELOG slimmed; stale
kb-init / continue-stream references removed; skill wire-vocab guard extended.
AGENTS.md / weknora-shared SKILL document retrieval_ready (a KB needs an
embedding model to be searchable), that --jq does not apply to NDJSON
streams, and the env-credential-first auth path; the KB quickstart example
now creates a retrieval-ready KB.

cli/internal/cmdutil/batch.go

@@ -40,7 +40,11 @@ func RunBatch(ctx context.Context, ids []string, op func(context.Context, string
 	for _, id := range ids {
 		select {
 		case <-ctx.Done():
-			outcomes = append(outcomes, BatchOutcome{ID: id, Err: ctx.Err()})
+			// Classify the context signal so the per-item envelope reports
+			// operation.cancelled / operation.timeout (ClassifyContextErr)
+			// instead of the generic internal.error, and an all-aborted batch
+			// exits by that class. Cause preserved so errors.Is still matches.
+			outcomes = append(outcomes, BatchOutcome{ID: id, Err: Wrapf(ClassifyContextErr(ctx.Err()), ctx.Err(), "operation on %s aborted", id)})
 			failed++
 			continue
 		default:
@@ -52,12 +56,18 @@ func RunBatch(ctx context.Context, ids []string, op func(context.Context, string
 		}
 	}
 	if failed > 0 {
+		// Any failure → operation.failed (exit 1). The aggregate code is
+		// deliberately coarse: the per-item batch envelope already carries each
+		// item's typed error (type + exit_code via ErrorToDetail), which is the
+		// authoritative per-item signal an agent should branch on. Collapsing
+		// "all failed with the same class" into that class was extra machinery
+		// for a convenience the per-item data already provides.
 		return outcomes, &Error{
 			Code:    CodeOperationFailed,
 			Message: fmt.Sprintf("%d/%d operation(s) failed", failed, len(ids)),
 			// Silent suppresses the stderr error envelope because the caller
 			// already emitted the batch envelope to stdout. The exit code
-			// still propagates via Error.Code → ExitCode (falls through to 1).
+			// still propagates via Error.Code → ExitCode.
 			Silent: true,
 		}
 	}