feat(controller-status): xcecli_ctrlstatus_primary authoritative reach-the-primary read (task 3.2)

.kiro/specs/controller-status/tasks.md

@@ -34,7 +34,7 @@
   - _Requirements: 1.1, 7.1, 7.2, 7.3_
   - _Boundary: libxce client_
   - _Depends: 1.1, 2.1, 2.2_
-- [ ] 3.2 Add the authoritative reach-the-primary status call
+- [x] 3.2 Add the authoritative reach-the-primary status call
   - Add a client call that returns only an authoritative reply (responder role == primary). When the first answer is from a non-primary, follow the redirect — target the reported primary via the reply's peer list, otherwise rotate the configured controller list — until the primary answers or the failover budget is exhausted.
   - TDD: a test where the first reachable node is a standby confirms the call follows the hint to the primary and returns a primary-role reply; a no-serving-primary test returns failure (never a standby hint as the authoritative result).
   - Observable: the authoritative call returns a reply whose responder role is primary even when a standby answered first, and fails (does not return a hint) when no primary serves.
@@ -70,3 +70,4 @@
 - 1.1 LEARNING (affects later tasks): the `$C.mapname(...)` capnp types are NOT auto-generated in this schema — the generated `controller.capnp.c` references HAND-AUTHORED C typedefs in `src/include/typemap.h` (same convention as `xce_clusterconf_t`). So `xce_ctrlstatus_t`/`xce_ctrlpeer_t` (and the `xce_reply_t.data.ctrlstatus` union member) live in `typemap.h`, verified field-for-field against the regenerated codec. `OPCode_ctrlstatus = 40`, `RequestReply_data_ctrlstatus = 12`. `configChecksum` is `xce_data_t*`. The handler/libxce tasks build/encode against these typemap.h types.
 - 2.1 LEARNING + SCHEMA AMENDMENT: capnp `Data` in THIS schema maps to the project's STRUCTURED `xce_data_t` union (table-switched), NOT raw bytes — `encode_Data_ptr` can't serialize a SHA-256 blob. So `configChecksum @6` was changed `Data → Text` (a 64-char lowercase-hex string of the full 32-byte `config_sha256`); typemap member is `char*`; freed in `ctrlstatus_free_fields`. Ordinal @6 unchanged, no released decoder yet → safe. Handler lives in NEW `src/controller/ctrlstatus.c` (`ctrlstatus_fill`/`ctrlstatus_free_fields`/`handle_ctrlstatus`), proto in `src/controller/include/cluster.h`, routed at `cluster.c` opcode switch, test `src/controller/testsuite/test_ctrlstatus.c` (registered in `controller_test.c`, built via `controller/meson.build`). `primary_host` read under `ha->lock`; peer name/host strings are BORROWED from myconf (not freed). The libxce client (3.x) decodes `configChecksum` as Text.
 - 3.1 LEARNING: the ctx-side reply union `xce_ctx_t.reply.u` (in `src/include/xcectx.h`) is SEPARATE from `xce_reply_t.data` (typemap.h) — the decode path needs BOTH a `ctrlstatus` member there AND a `case OPCode_ctrlstatus` in `xcectx.c` handle_reply (mirror clusterconf). Free: clusterconf's `xce_free_clusterconf` macro is a LATENT-BROKEN alias (undefined symbol, never expanded); use the REAL generated free — `xce_free_ctrlstatus(s) → free_CtrlStatus(s)`, `xcecli_free_ctrlstatus(s) → xce_free_ctrlstatus(s)` (any TU expanding it must include the generated `controller.capnp.h`). `xcecli_ctrlstatus` is is_write=false; NULL ctx → `-EINVAL`.
+- 3.2: `xcecli_ctrlstatus_primary` = bounded loop (cap `failover.retry.max_retries`) reusing `xcecli_ctrlstatus` + `xce_ctx_capture_redirect_hint` (map `primaryName`→addr via `peers[]`, else master rotation); authoritative iff `responderRole == CTRL_PRIMARY` (== 0; `ctrl_role_t` PRIMARY=0/STANDBY=1/INIT=2/ELECTING=3 in `ha.h` — REVALIDATION TRIGGER: a role-enum reorder breaks the pinned wire ordinal `XCECLI_CTRLSTATUS_ROLE_PRIMARY=0`). On exhaustion → `-E_XCE_NOT_READY`, `*status` untouched (never a hint). Pure helpers `xcecli_ctrlstatus_is_authoritative`/`_primary_addr` unit-tested; live standby→primary redirect is 5.1.