esp/gizclaw: Remove the local timespec_get shim

[idy]

Background

This issue supersedes h2vivi/firmwares#430 using the current GizOS ESP integration.

ESP-IDF 6.0's selected ESP32-S3 picolibc headers declare timespec_get(), but the target archives do not define it. GizOS currently links by carrying native_component_src/esp-idf6.x/h2_gizclaw/src/h2_esp_gizclaw_time_compat.c, a weak local definition of a standard C library symbol. Espressif accepted the diagnosis in espressif/esp-idf#18889 and is tracking the upstream implementation in open PR espressif/esp-idf#18890. The GizClaw C SDK still references timespec_get() in its default platform, even though GizOS injects its own PAL-backed clock for the client.

Goal

Consume an owning upstream portability fix and delete the GizOS-local weak timespec_get() ABI shim while keeping every maintained ESP32-S3 GizClaw firmware linkable.

Non-goals

• Do not switch the repository from picolibc to newlib.
• Do not retain the shim in another board, launcher, component or library.
• Do not change GizClaw deadline semantics or replace monotonic time with wall-clock time in the injected GizOS platform.
• Do not advance the pinned ESP-IDF or GizClaw revision without reviewing the full immutable dependency diff and native build matrix.

Code Changes Tree

tools/bazel/native_versions/esp_idf_commit.txt             # pin the first reviewed ESP-IDF revision that contains the upstream libc fix when that route is selected
tools/bazel/tests/test_external_native_roots.py             # reject a reintroduced local standard-library compatibility symbol in GizOS components
MODULE.bazel                                               # update the immutable GizClaw revision only if the owning SDK portability fix is the selected route
MODULE.bazel.lock                                          # synchronize the selected immutable upstream revision and integrity metadata
native_component_src/esp-idf6.x/h2_gizclaw/src/h2_esp_gizclaw_time_compat.c # (delete) remove the weak local timespec_get definition
guides/zh/developing/bazel.md                              # record the final ESP-IDF/GizClaw revision and link-validation boundary
guides/zh/developing/components/esp_idf6_x.md              # document that the ESP GizClaw component no longer owns libc ABI symbols

The component BUILD rule already discovers tracked component sources; deleting the compatibility file must remove it from both Bazel-declared native inputs and ESP-IDF CMake source projection without adding an empty replacement.

Design

Owning fix selection

Prefer the reviewed Espressif libc implementation once PR #18890 is present in a supported pinned ESP-IDF revision. If that cannot be consumed independently of a broader unsupported SDK update, fix the GizClaw default-platform portability in GizClaw/gizclaw and update GizOS to that immutable revision. In either route, the final GizOS tree contains no implementation of timespec_get().

The selected route and revision must be recorded in the Issue/PR with evidence that the defining symbol comes from its owning upstream archive or that no selected GizClaw object references it.

Clock boundary

libs/gizclaw continues to inject h2_pal_time_get_monotonic_ms() through gzc_platform_t.time_instant_ms. Removal of the default-platform link defect must not change that runtime clock owner or the bounded writer/platform contract.

Failure behavior

Unsupported SDK revisions, absent libc symbols, duplicate strong/weak definitions and accidental fallback to a host libc must fail during the exact ESP firmware link. A host test or Bazel query is not sufficient proof.

Test And Acceptance Criteria

Acceptance Criteria

• The selected pinned upstream revision owns the portability fix and its immutable revision/integrity is recorded.
• GizOS contains no definition, declaration override or linker injection for a local timespec_get() implementation.
• libs/gizclaw still injects the PAL monotonic clock and its host contract tests pass.
• Maintained ESP32-S3 GizClaw firmware images link without an undefined or duplicate timespec_get symbol.
• No unrelated SDK, libc or time-semantics change is bundled with the cleanup.

Validation

rg -n "timespec_get" native_component_src boards projects libs
bazel mod deps --lockfile_mode=error
bazel test --config=macos_arm64 //libs/gizclaw:all
bazel build --config=esp32s3 //projects/example/targets/h2loader_tar_zlib/gizclaw-ping-speed/amoled:package
make guides-build
git diff --check

• Inspect the final ESP32-S3 link map/archive symbols to prove the symbol owner or absence of the reference.
• If the owning upstream change is not yet available in a supported revision, record BLOCKED with the upstream PR and keep this Bug open; do not remove the only linkable workaround prematurely.