Re-land (#5515) Include ROCm base version in TheRock manifest

[erman-gurses]

Reland #5515
Reverted at #5527

Include ROCm base version in TheRock manifest

Add an optional rocm_version field to generated manifests by
deriving the base semantic version from rocm_package_version.

Examples:

• 7.14.0a20260526+a0 -> 7.14.0
• git -> no rocm_version field emitted

This keeps manifest generation self-contained while providing
normalized version metadata for downstream CI/CD consumers.

Validated:

• direct manifest generation
• THEROCK_PACKAGE_VERSION=git
• versioned package builds
• therock-aux-overlay CMake integration path

Local Validation

Validated both manifest generation paths locally:

1. Direct manifest generation

Verified that:

python build_tools/generate_therock_manifest.py \
  --rocm-package-version git

correctly emits:

"rocm_package_version": "git"

without generating rocm_version.

Also verified that:

python build_tools/generate_therock_manifest.py \
  --rocm-package-version 7.14.0a20260526+a0

correctly emits:

"rocm_package_version": "7.14.0a20260526+a0",
"rocm_version": "7.14.0"

2. CMake integration path

Validated the actual therock-aux-overlay manifest generation path with:

cmake -S . -B build-min -GNinja \
  -DTHEROCK_PACKAGE_VERSION=git \
  -DTHEROCK_AMDGPU_FAMILIES=gfx94X-dcgpu

cmake --build build-min --target therock-aux-overlay

Result:
TheRock/build-min/base/aux-overlay/build/therock_manifest.json

{
  "the_rock_commit": "1e2662a33dc2a7cbec82f72de285fe00c823c5f0",
  "rocm_package_version": "git",
  "submodules": [
    {
      "submodule_name": "half",
      "submodule_path": "base/half",
      "submodule_url": "https://github.com/ROCm/half.git",
      "pin_sha": "207ee58595a64b5c4a70df221f1e6e704b807811",
      "patches": []
    },
 ...   

and:

cmake -S . -B build-min-version -GNinja \
  -DTHEROCK_PACKAGE_VERSION=7.14.0a20260526+a0 \
  -DTHEROCK_AMDGPU_FAMILIES=gfx94X-dcgpu

cmake --build build-min-version --target therock-aux-overlay

Result:
TheRock/build-min-version/base/aux-overlay/build/therock_manifest.json

{
  "the_rock_commit": "1e2662a33dc2a7cbec82f72de285fe00c823c5f0",
  "rocm_package_version": "7.14.0a20260526+a0",
  "rocm_version": "7.14.0",
  "submodules": [
    {
      "submodule_name": "half",
      "submodule_path": "base/half",
      "submodule_url": "https://github.com/ROCm/half.git",
      "pin_sha": "207ee58595a64b5c4a70df221f1e6e704b807811",
      "patches": []
    },
...

Both builds completed successfully and generated the manifest correctly.

3. CI Result:

https://therock-ci-artifacts.s3.amazonaws.com/26666604312-linux/manifests/therock_manifest.json