* Fix EC Volumes page header styling to match admin theme
Fixes#7779
The EC Volumes page was rendering with bright Bootstrap default colors
instead of the admin dark theme because it was structured as a standalone
HTML document with its own DOCTYPE, head, and body tags.
This fix converts the template to be a content fragment (like other
properly styled templates such as cluster_ec_shards.templ) so it
correctly inherits the admin.css styling when rendered within the layout.
* Address review comments: fix URL interpolation and falsy value check
- Fix collection filter link to use templ.URL() for proper interpolation
- Change updateUrl() falsy check from 'if (params[key])' to
'if (params[key] != null)' to handle 0 and false values correctly
* Address additional review comments
- Use erasure_coding.TotalShardsCount constant instead of hardcoded '14'
for shard count displays (lines 88 and 214)
- Improve error handling in repairVolume() to check response.ok before
parsing JSON, preventing confusing errors on non-JSON responses
- Remove unused totalSize variable in formatShardRangesWithSizes()
- Simplify redundant pagination conditions
* Remove unused code: displayShardLocationsHTML, groupShardsByServerWithSizes, formatShardRangesWithSizes
These functions and templates were defined but never called anywhere
in the codebase. Removing them reduces code maintenance burden.
* Address review feedback: improve code quality
- Add defensive JSON response validation in repairVolume function
- Replace O(n²) bubble sorts with Go's standard sort.Ints and sort.Slice
- Document volume status thresholds explaining EC recovery logic:
* Critical: unrecoverable (more than DataShardsCount missing)
* Degraded: high risk (more than half DataShardsCount missing)
* Incomplete: reduced redundancy (more than half ParityShardsCount missing)
* Minor: fully recoverable with good margin
* Fix redundant shard count display in Healthy Volumes card
Changed from 'Complete (14/14 shards)' to 'All 14 shards present' since
the numerator and denominator were always the same value.
* Use templ.URL for default collection link for consistency
* Fix Clear Filter link to stay on EC Volumes page
Changed href from /cluster/ec-shards to /cluster/ec-volumes so clearing
the filter stays on the current page instead of navigating away.