Badges (#6170)

* Fix Release Progress badges and workflow

- Fix update-progress.py to output blocker/mustdo counts in correct format
  The workflow expects blocker_done=, blocker_total=, mustdo_done=, mustdo_total=
  output lines but the script was only outputting human-readable format

- Update README badge links to point to project view 24 instead of base project

This fixes the workflow failures where BLOCKER_DONE and the related environment
variables were not being set, causing badge updates to fail.

The badges were pointing to old unmaintained gists under user X.
Updated to use the gist automatically maintained by the Release Progress
workflow (gist ID: 0ad2eabb63b28eb90d69f5e5b2c1496f).

The workflow now successfully updates these badges every 4 hours with
current release blocker and must-do progress.

The script now auto-detects the HDF5 version from src/H5public.h and
filters release blockers/must-do items by milestone matching that version.

Changes:
- Added get_hdf5_version_from_header() to read version from H5public.h
- Updated GraphQL query to fetch milestone information from issues
- Added milestone filtering logic to only count items for the target release
- Made validation more lenient when using milestone filter (allows 0/0)
- Added MILESTONE_FILTER environment variable for manual override

For develop branch with version 2.1.0 in H5public.h, this will now only
count items with milestone containing "2.1" (e.g., "2.1.0", "HDF5 2.1").

* Add version number to badge labels

The badges now display the version (e.g., "2.1 Release Blockers" instead
of just "Release Blockers") when filtering by milestone.

Changes:
- Python script outputs version to GitHub Actions
- Workflow passes version to badge generation script
- Badge script includes version in label if available
- Labels show "X.Y Release Blockers" / "X.Y Release Must Do"


The three badges now track:
1. Release Blockers - Critical issues that must be resolved
2. Release Must Do - Important items for the release
3. Release Nice to Have - Optional improvements for the release

All three badges show version prefix (e.g., "2.1") and support 0/0
display when no items exist for a milestone.

---------

Co-authored-by: Claude Sonnet 4.5 <noreply@anthropic.com>

README.md

@@ -94,11 +94,13 @@ least one annual release for each maintenance branch.
 
 ### Release Progress
 
-[![Release Blockers](https://img.shields.io/endpoint?url=https://gist.githubusercontent.com/brtnfld/a4fbdde293677bf3f63f3cfd3aef6b44/raw/release-blockers.json)](https://github.com/orgs/HDFGroup/projects/39/views/24)
+[![Release Blockers](https://img.shields.io/endpoint?url=https://gist.githubusercontent.com/HDFGroup-Bot/0ad2eabb63b28eb90d69f5e5b2c1496f/raw/release-blocker-hdf5.json)](https://github.com/orgs/HDFGroup/projects/39/views/24)
 
-[![Release Must Do](https://img.shields.io/endpoint?url=https://gist.githubusercontent.com/brtnfld/8a077a919d048ce5dc9f56350bec10bc/raw/release-mustdo.json)](https://github.com/orgs/HDFGroup/projects/39/views/24)
+[![Release Must Do](https://img.shields.io/endpoint?url=https://gist.githubusercontent.com/HDFGroup-Bot/0ad2eabb63b28eb90d69f5e5b2c1496f/raw/release-mustdo-hdf5.json)](https://github.com/orgs/HDFGroup/projects/39/views/24)
 
-The badges above show the current progress of **release-blocking** and **must-do** issues with colors that reflect completion status:
+[![Release Nice to Have](https://img.shields.io/endpoint?url=https://gist.githubusercontent.com/HDFGroup-Bot/0ad2eabb63b28eb90d69f5e5b2c1496f/raw/release-nicetohave-hdf5.json)](https://github.com/orgs/HDFGroup/projects/39/views/24)
+
+The badges above show the current progress of **release-blocking**, **must-do**, and **nice-to-have** issues with colors that reflect completion status:
 
 - 🟢 **Green (90%+)**: Readying for Deployment - most issues completed
 - 🟡 **Yellow (60-89%)**: Nearing Completion - on track for release