fix(agc): gate bulk capture profiling and retain cache regressions - #50

Bulk shader-memory reads now respect CaptureProfiled() before updating read totals, matching the scalar read path. This branch also checks that cached plans rebuild their compact evaluation data and that cached bulk reads report only the requested words across a page boundary, including repeated captures.

Two commits on main 8856f180ca0b5605574842666ffbc8b0bb69cc4d; head 2098259a7813566243f83a1458321b44d054cdb5. Main already includes the compact-plan implementation from boykopovar#1193, so this refresh retains only the profiling correction and additional regressions. Shader cache format 36 is unchanged.

Validation: Linux x86-64 Release build of full runtime libraries and the selected test executables. With APS5_VERIFY_SRT_COMPACT=1, all 20 selected cache, shader-memory and prepared-shader/graphics CTest cases passed on both Radeon RX 6650 XT (RADV Mesa 26.2.4) and lavapipe, with zero skips. The negative controls and restored-source reruns were completed on base a08de6827; the complete build and both positive 20-case sets were repeated after the rebase onto 8856f180c. Conventions and whitespace checks pass.

The unchanged regression sources detect both deliberate production faults: removing cache-load CompactPlan fails with “the cached plan lost compact evaluation data”; marking entire cached pages as read fails with “an unaligned cached run recorded unrelated words”. Test executables were rebuilt against each faulty implementation, then the production sources were restored and rebuilt. The exact-span case runs through agc_shader_bindless; the cache round-trip case runs through agc_shader_disk_cache.

The local validation build differs from this public head only by a private SPIRV-Tools teardown repair in the submodule. That dependency change is excluded from this PR; these results do not independently validate the official dependency pin. No current Windows/full-suite or title FPS result is claimed.

• Depends on: none (perf(agc): cheaper shader-memory captures per draw boykopovar/AnyPS5#1193 is merged)
• Unblocks: none
• GPUs tested: AMD Radeon RX 6650 XT, RADV Mesa 26.2.4, Linux 7.2.9; lavapipe Mesa 26.2.4, Linux
• AI-assisted: yes