* fix(rust-volume): remove .ecsum sidecars on EC destroy / shard delete
Rust EcVolume::destroy removed shards and .ecx/.ecj/.vif but left bitrot
checksum sidecars (.ecsum / .ecsum.v*). On clusters that run weed-volume
(not Go weed volume), collection.delete therefore orphans every sidecar
while correctly wiping shards — observed live on 4.39 (14/14 .ecsum
survived after collection.delete on a freshly encoded EC volume).
Go Destroy already calls RemoveBitrotSidecars; this brings Rust to parity:
- hoist remove_bitrot_sidecars into ec_bitrot (shared helper)
- call it from EcVolume::destroy for dir / dir_idx / ecx_actual_dir
- call it from Store::delete_ec_shards when a disk has no remaining shards
- unit test: test_destroy_removes_bitrot_sidecar
* rust volume: gate the shard-delete sidecar sweep on a local shard removal
Only sweep a disk's .ecsum when this delete actually removed a shard file
there, matching Go's found gate: a delete that never touched a disk must not
strip a sidecar it does not own — a shared -dir.idx sibling with surviving
shards, or an ec.rebuild index-prep copy that lands .ecx/.ecsum before any
shard. The shard-presence probe now treats unexpected stat errors as
"exists" so a transient failure cannot orphan-classify live shards, and
check_all_ec_shards_deleted reuses it.
* rust volume: destroy() sidecar sweep needs only the data and idx bases
ecx_actual_dir is always one of the two, so the third branch could never
run; this is now exactly Go Destroy()'s two-base sweep.
* rust volume: call the shared sidecar removal helper directly
* rust volume: unit-test remove_bitrot_sidecars
Mirrors Go's TestRemoveBitrotSidecars: legacy and versioned sidecars are
removed, a shard file and a longer-vid sidecar survive, absent is success.
* rust volume: keep the shared idx-base sidecar while a sibling disk has shards
One -dir.idx serves every location, so emptying one disk must not sweep
<idx>/<vol>.ecsum out from under a sibling that still holds shards. Nothing
reads the idx-base sidecar today, but .ecx shows index-dir files are real;
this keeps the defensive sweep safe if a writer ever lands one there.
* ec shard delete: keep the shared idx-base sidecar while a sibling disk has shards
One -dir.idx serves every disk, so emptying one disk must not sweep
<idx>/<vol>.ecsum out from under a sibling that still holds shards of the
volume — the same gate the Rust volume server applies. A status error counts
as in-use so a transient failure never strips it early.
* rust volume: drop a shard-only disk's stale .vif with the node's last shard
Go's removeEcSharedIndexFiles also clears the data-base .vif in the
all-shards-gone pass, gated on .idx absence so a disk still hosting the
source volume keeps its live .vif; the Rust delete path left it behind.
Unexpected stat errors count as .idx-present so a transient failure never
strips a live volume's .vif.
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Co-authored-by: Chris Lu <chris.lu@gmail.com>