* Fix Python module shadowing in Docker CI
Applies legacy_create_init = False to Python rules in BUILD files to prevent Bazel from automatically generating __init__.py files. This prevents the root 'signal/' directory (which contains C++ kernels but no Python source) from being treated as a Python package, which was shadowing the standard library 'signal' module and causing psutil failures in the tflm-ci Docker container.
* Fix directory path in Docker workflows
* Refactor CI to use platform-based suites
* Consolidate Xtensa workflows into suite_xtensa.yml
* Consolidate Cortex-M, Hexagon, and RISC-V workflows
* Split ci.yml into smaller reusable workflows
* Rename run_ci.yml to run_basics.yml
* Rename ci_*.yml to test_*.yml
* Rename riscv.yml to run_riscv.yml
* Refactor CI structure: Rename suites/runners and remove Cortex-M from core
* Standardize test scopes to basic, extended, all
* Update scopes and comments for CI workflows
* Move check-tflite-files to PR workflows
* Optimize pr_full.yml to run only extended tests
* Fix incorrect dependency name in run_core.yml
