fix(gazelle): migrate to official tree-sitter Go bindings

[dougthor42]

Replace the unmaintained github.com/smacker/go-tree-sitter dependency with the official github.com/tree-sitter/go-tree-sitter and github.com/tree-sitter/tree-sitter-python (v0.25.0) modules. This updates the Python grammar so the Gazelle plugin can parse Python 3.14 PEP 758 unparenthesized multi-exception except clauses without errors.

Because the official bindings include C sources across parent and subdirectory paths that standard go_repository Gazelle generation cannot compile directly, fetch both modules via http_archive with custom cc_library and go_library targets in both Bzlmod and WORKSPACE modes.

We also remove unneeded go_repository items from gazelle/deps.bzl.

Generated by Gemini. Tested on our large-scale QuantumAI monorepo.

TAG=agy

Timing

I ran the parent commit and this PR on our primary QuantumAI monorepo. This PR might make things a little faster, but I didn't want to wait for 5 or more runs in hyperfine 😆.

Parent commit:

$ git -C ../../oss/bazel-contrib/rules_python rev-parse HEAD
b7ec5bd151df5f725ab8f76446fd548ac4fedce1  # agents: require user-visible docs prose and workaround comments (#4271)
$ hyperfine --warmup=1 --runs=3 'bazel run --bes_backend= //:gazelle'
Benchmark 1: bazel run --bes_backend= //:gazelle
  Time (mean ± σ):     93.052 s ± 18.023 s    [User: 99.884 s, System: 6.302 s]
  Range (min … max):   82.134 s … 113.855 s    3 runs

  Warning: Statistical outliers were detected. Consider re-running this benchmark on a quiet system without any interferences from other programs. It might help to use the '--warmup' or '--prepare' options.

This PR:

$ git -C ../../oss/bazel-contrib/rules_python rev-parse HEAD
bc5b12a5e160e7f91f665fc730b9b305dc3471b4
$ hyperfine --warmup=1 --runs=3 'bazel run --bes_backend= //:gazelle'
Benchmark 1: bazel run --bes_backend= //:gazelle
  Time (mean ± σ):     80.338 s ±  2.570 s    [User: 80.271 s, System: 3.808 s]
  Range (min … max):   78.292 s … 83.223 s    3 runs

Fixes #3416