pgxp: emit hook macros + dual build targets + flavor-namespaced caches (phase 2)

Emitter side of the value-propagation engine (ENHANCEMENTS.md G1.10):

- recompiler/src/pgxp_hook_emitter.{h,cpp} (new, in the codegen-hash
  surface): ONE hook grammar shared by BOTH emitters, wrapping loads/
  stores/COP2 transfers and precision-carrying ALU ops (moves, add/sub,
  or-merge, shifts, LUI, HI/LO, muldiv) with PGXP_*() macros. Clobberable
  sources are captured into locals before the statement. Precision-
  destroying ops (AND/XOR/SLT/...) are deliberately unhooked - validate-
  on-read drops their stale shadows for free.
- code_generator.cpp: central append in translate_instruction; LWC2/SWC2
  emissions capture the RAW loaded/stored word (a masked GTE register
  write must validate against the word as loaded).
- strict_translator.cpp: translate() wraps translate_impl()'s c_code with
  the shared grammar; deferred load-delay variants hook the psx_ldd temp.
- BIOS regenerated, fingerprints verified CHANGED (SCPH1001 + OpenBIOS;
  42.6k/12.2k macro sites). Base runtime + 33/33 tests green against it.
- Gating: macros expand only under -DPSX_PGXP=1. runtime.cmake grows a
  PGXP option on psxrecomp_add_runtime_target (defines PSX_PGXP=1 +
  PSX_OVERLAY_FLAVOR=2, _pgxp exe suffix) and PSX_PGXP_VARIANT to build
  the sibling target from the same generated tree (framework runtime +
  game wrapper). No ABI version bump needed: the appended PGXPHooks
  table is NULL-tolerant and the flavor half of the ABI tag rejects any
  host/DLL flavor mix.
- Shard caches: flavor folded into the cache tag (cg<V>_<hash>_gc<hash>
  _f<flavor>) in overlay_loader.c + compile_overlays.py so base and pgxp
  caches never share a directory; compile_overlays.py passes
  -DPSX_PGXP=1 when flavor bit 2 is set; overlay preamble forwards
  psx_pgxp_* through the table. PSX_OVERLAY_CODEGEN_VER 9 -> 10.
- Env overrides PSX_GEOMETRY_CORRECTION / PSX_PERSPECTIVE_TEXTURING /
  PSX_PGXP_CPU_MODE (validation path: free-running headless boots arm
  from the first vertex); census grew produced/swc2_stores and the pgxp
  verb reports suppress/active gate state.

Validated: PSXRecomp_pgxp.exe boots the recompiled BIOS with hooks armed
(engine active, per-vertex lookups flowing; the BIOS shell has no RTPS
content so produced=0 there is correct - coverage measurement moves to a
3D title in phase 3).

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>

runtime/src/debug_server.c

@@ -5212,7 +5212,8 @@ static void handle_geom_correction(int id, const char *json)
              "\"pgxp\":{\"enabled\":%d,\"cpu_mode\":%d,\"tolerance\":%.3f,"
              "\"lookups\":%llu,\"dataflow_hit\":%llu,\"fallback_hit\":%llu,"
              "\"native\":%llu,\"value_mismatch\":%llu,\"trunc_reject\":%llu,"
-             "\"tolerance_reject\":%llu,\"w_valid\":%llu}}",
+             "\"tolerance_reject\":%llu,\"w_valid\":%llu,"
+             "\"produced\":%llu,\"swc2_stores\":%llu}}",
              id,
              gte_geometry_correction_enabled(),
              (unsigned)hits,
@@ -5226,7 +5227,9 @@ static void handle_geom_correction(int id, const char *json)
              (unsigned long long)ps.value_mismatch,
              (unsigned long long)ps.trunc_reject,
              (unsigned long long)ps.tolerance_reject,
-             (unsigned long long)ps.w_valid);
+             (unsigned long long)ps.w_valid,
+             (unsigned long long)ps.produced,
+             (unsigned long long)ps.swc2_stores);
 }
 
 /* pgxp — live-tune the value-propagation engine for one-toggle isolation runs
@@ -5260,8 +5263,9 @@ static void handle_pgxp(int id, const char *json)
             pgxp_set_tolerance((float)strtod(p, NULL));
     }
     send_fmt("{\"id\":%d,\"ok\":true,\"enabled\":%d,\"cpu_mode\":%d,"
-             "\"tolerance\":%.3f}",
-             id, pgxp_enabled(), pgxp_cpu_mode(), (double)pgxp_tolerance());
+             "\"tolerance\":%.3f,\"suppress\":%u,\"active\":%d}",
+             id, pgxp_enabled(), pgxp_cpu_mode(), (double)pgxp_tolerance(),
+             (unsigned)pgxp_test_suppress_depth(), pgxp_test_active());
 }
 
 static void handle_gpu_state(int id, const char *json)