## Problem
`/analytics` Hash Usage Matrix 1-byte view excluded repeaters configured
for 2- or 3-byte hash prefixes. In MeshCore, 1-byte path-matching is a
first-byte equality check, so any packet routed by 1-byte hash collides
on that first byte regardless of the downstream repeater's configured
prefix size. Omitting multi-byte prefix repeaters under-reports real
conflicts in the 1-byte hash space.
## Fix
**Data layer — `cmd/server/store.go` (`computeHashCollisions`,
~L7907-L7918 before, L7907-L7941 after):**
Before — `one_byte_cells` was populated only from `prefixMap`, which
only contained repeaters with `hash_size == 1`:
```go
if bytes == 1 {
oneByteCells = make(map[string][]collisionNode)
for i := 0; i < 256; i++ {
hex := strings.ToUpper(fmt.Sprintf("%02x", i))
oneByteCells[hex] = prefixMap[hex]
if oneByteCells[hex] == nil {
oneByteCells[hex] = make([]collisionNode, 0)
}
}
} else if bytes == 2 { ... }
```
After — additionally project all `hash_size in {2,3}` repeaters to their
first byte:
```go
if bytes == 1 {
// ... (same baseline population) ...
for _, cn := range allCNodes {
if cn.Role != "repeater" { continue }
if cn.HashSize != 2 && cn.HashSize != 3 { continue }
if len(cn.PublicKey) < 2 { continue }
hex := strings.ToUpper(cn.PublicKey[:2])
if _, ok := oneByteCells[hex]; !ok { continue }
oneByteCells[hex] = append(oneByteCells[hex], cn)
}
}
```
The 2-byte view's bucketing is unchanged — that view continues to count
only repeaters configured for 2-byte prefixes (those semantics differ).
**UI — `public/analytics.js` L1459:** clarified the 1-byte view
description so the inclusion of multi-byte prefix repeaters is explicit.
## API shape
No response-shape change. `one_byte_cells[HEX]` is still
`[]collisionNode`; only the contents now include 2/3-byte prefix
repeaters in the appropriate first-byte buckets. The existing frontend
decoder is unaffected.
## Tests
-
`cmd/server/routes_test.go::TestHashCollisionsOneByteIncludesMultiBytePrefixRepeaters`
— seeds three repeaters with first byte `CC` configured for 1/2/3-byte
prefixes plus an unrelated `DD` repeater, asserts all three appear in
`one_byte_cells["CC"]`, and that the 2-byte view's `nodes_for_byte` is
unchanged.
Red commit `278bdf8d` (test only) fails on assertion ("got 1, want 3");
green commit `9127ea4e` passes.
## Preflight
`bash ~/.openclaw/skills/pr-preflight/scripts/run-all.sh origin/master`
→ clean.
Closes#1218
---------
Co-authored-by: clawbot <bot@corescope>
