chore: kill fuji — no Avalanche/Fuji terminology

Per canonical rule: Lux is its own thing, fuji isn't ours. Sweep
removes positive references to the Avalanche testnet name from
comments, function names, test fixtures, and example data. Where
defensive code rejects non-Lux HRPs (lux/genesis), the test input
swapped from 'P-fuji1...' to 'P-avax1...' so the rejection behavior
still proves out without naming fuji as a thing.

Build clean.

cmd/bootstrap-l2/main.go

@@ -23,7 +23,7 @@
 // never aliased:
 //
 //   - `networkID` — identifies a validator network. Comes in two scopes:
-//       * primary networkID (uint32: 1=mainnet, 2=fuji, 3=local, 1337=dev)
+//       * primary networkID (uint32: 1=mainnet, 2=testnet, 3=local, 1337=dev)
 //       * per-chain networkID (ids.ID 32 bytes) — the CreateNetworkTx ID
 //         that owns one or more chains.
 //   - `chainID` — the blockchain's own globally unique ID (ids.ID 32 bytes).

pkg/genesis/params.go

@@ -300,7 +300,7 @@ func GetBootstrappersFromKeys(keysDir string) ([]Bootstrapper, error) {
 }
 
 // allowedHRPs is the closed set of bech32 HRPs that ParseAddress accepts.
-// Any other HRP (notably "avax"/"fuji" from upstream Avalanche or arbitrary
+// Any other HRP (notably "avax" from upstream Avalanche or arbitrary
 // user HRPs) is a wrong-network event — the same 20 bytes silently re-encoded
 // under a foreign HRP must not be admitted into a Lux genesis.
 var allowedHRPs = map[string]struct{}{

pkg/genesis/params_test.go

@@ -12,7 +12,7 @@ import (
 
 // TestParseAddress_HRPWhitelist locks in that ParseAddress accepts only the
 // canonical Lux HRPs (lux/test/dev/local). Any other HRP — notably an upstream
-// "avax"/"fuji" address copy-pasted into a Lux genesis — must be rejected with
+// "avax" or other non-lux address copy-pasted into a Lux genesis — must be rejected with
 // a clear error rather than silently re-encoded into a lux1... allocation.
 func TestParseAddress_HRPWhitelist(t *testing.T) {
 	tests := []struct {
@@ -39,9 +39,9 @@ func TestParseAddress_HRPWhitelist(t *testing.T) {
 			wantErr: `unsupported HRP "avax"`,
 		},
 		{
-			name:    "reject P-fuji (fuji HRP not allowed)",
-			addr:    "P-fuji1ck0t9h5u7jvvzhx29n99guqjsfkpzt67cr6m3y",
-			wantErr: `unsupported HRP "fuji"`,
+			name:    "reject non-lux HRP",
+			addr:    "P-avax1ck0t9h5u7jvvzhx29n99guqjsfkpzt67cr6m3y",
+			wantErr: `unsupported HRP "avax"`,
 		},
 
 		// Reject: empty.