feedback5 WU: 焰狐龙梓兰 (MH05) leaves data/assets.json; a voice slot with no line on disk is dropped, not []

She left the 自选 pool in 0.2.0 (data/backups.json diy.excluded, a collab operator) but her art stayed in the
manifest because fetch-assets refuses to shrink it. Regenerated offline in this worktree, whose public/assets and
public/fonts are the shared ones: node tools/fetch-assets.mjs --offline --add-only --allow-shrink (--add-only so no
file on disk is rewritten and the fonts entry is kept). The run dropped exactly her 163 entries.

JSON diff against the previous manifest: removed chars.char_1048_orchd2, skills.skchr_orchd2_1..3,
skillsById.skchr_orchd2_1..3, audio.sfx.units.char_1048_orchd2; changed hash and stats (files 6994 -> 6979,
bytes 462620448 -> 458334505, chars 210 -> 209, charsWithBack 207 -> 206, spineModels 673 -> 671,
skills 525 -> 522, sfxUnits 484 -> 483); nothing added, nothing else changed.

The first regeneration also added 71 entries like audio.voice.char_134_ifrit = {select: [], place: []}: the 自选
operators' voice lines are planned but not downloaded on this machine, and resolveTemplate kept an array whose lines
were all missing as []. tools/assets/manifest.mjs now drops such an array like a missing leaf (and the entry it
empties); an array that is empty in the template stays.

Tests: test/assets.test.js (the array rule), test/assets-diy.test.js (no diy.excluded operator keeps art in the
manifest). docs/ASSETS.md: 71 自选 picks, 209 operators (206 with Back), 522 skill icons, the empty-slot rule.

docs/ASSETS.md

@@ -99,7 +99,7 @@ The `stem` of a Spine model is the upstream file name. Two examples: `char_107_l
 
 ### Id scope
 
-- **Operators:** all 138 pool charIds from `activity_table` (`charShopChessDatas[*].charId ∪ backupCharId`), including hidden chess and backup operators; plus every unit of `data/backups.json` research 07 does not list — the 72 自选 owned-6★ picks (`diy.ownedPool`, DATA.md §18; the collab operators are not in the data) — planned from 07's URL patterns (`tools/assets/plan.mjs patternOperator`, `tools/fetch-assets.mjs dataExtras`): avatar and portrait (E0–E1 and E2), the default-skin battle Spine Front / Back, the icon and skill sound of each skill, the sub-profession icon. 210 operators in all (207 with a Back model).
+- **Operators:** all 138 pool charIds from `activity_table` (`charShopChessDatas[*].charId ∪ backupCharId`), including hidden chess and backup operators; plus every unit of `data/backups.json` research 07 does not list — the 71 自选 owned-6★ picks (`diy.ownedPool`, DATA.md §18; the collab operators are not in the data, and 焰狐龙梓兰's entries left the manifest when she left the pool in 0.2.0) — planned from 07's URL patterns (`tools/assets/plan.mjs patternOperator`, `tools/fetch-assets.mjs dataExtras`): avatar and portrait (E0–E1 and E2), the default-skin battle Spine Front / Back, the icon and skill sound of each skill, the sub-profession icon. 209 operators in all (206 with a Back model).
 - **Tokens:** the 20 pool tokens, and the 38 summons of the 自选 picks (`data/backups.json tokens`) as extra tokens (below): their avatars; their battle Spine exists upstream only as skin variants, which the default locations miss — no Spine yet (the client draws the avatar).
 - **Enemies:** 253 ids planned, 252 in the manifest (心烛 has no assets). The set is the union of:
   - the 07 enemy list;
@@ -111,7 +111,7 @@ The `stem` of a Spine model is the upstream file name. Two examples: `char_107_l
   - enemy units spawned by operator kits (research 03 skills/talents). For example, 隐德来希's default S3 summons 心烛 `enemy_5601_entlec` through the talent key `take_extra_enemy_key`. 心烛 has no icon and no Spine in any dump, so it has no manifest entry: it is reported as a miss, and the client must draw a glyph.
 - **Extra tokens:** any `token_*` key of `data/tokens.json` that research does not list gets the default avatar and Spine locations.
   - The non-token summons in that file (`enemy_9012_acloon` 炎佑, `char_605_cmedic`, `char_613_acmedc`) are found under `enemies` and `chars`.
-- **Skill icons:** every skill index of every planned operator (the default one first; DESIGN §16 loadouts, the 自选 picks' three skills): 525 icons.
+- **Skill icons:** every skill index of every planned operator (the default one first; DESIGN §16 loadouts, the 自选 picks' three skills): 522 icons.
 - **UI:**
   - every group from `07-assets.json → autochessUi`: rarity, elite and chess-level sprites, the shop panel and cards, HUD, bond board, equip slot, round dialog, band choose, settlement, prepare backdrop;
   - `arts` (rarity stars, elite icons, the camp logos of pool nations, the loading illustrations used by the act2 modes, battle common sprites, act2 entry backdrops and season logo, item rarity frames);
@@ -174,7 +174,8 @@ All paths are URL paths relative to the site root, for example `/assets/char/ava
                            resultFour, resultThree, resultTwo, resultLose } },
                            // 干员战斗语音: an operator's official battle lines (charword_table.json placeType → slot,
                            // tools/assets/audio.mjs VOICE_SLOTS); a slot with several lines is an array and the client
-                           // draws one (public/js/audio.js voice). Only these twelve ever play (DESIGN §21.30): the
+                           // draws one (public/js/audio.js voice); a slot whose lines are all missing on disk is left
+                           // out (an operator with none has no entry), never an empty array. Only these twelve ever play (DESIGN §21.30): the
                            // prep-only slots 干员报到 / 编入队伍 / 任命队长 are left out of the plan by default —
                            // nothing requests them and they cost 360 files (19.3 MB) per run — and `--voice-all` adds
                            // them (audio.mjs VOICE_PREP_SLOTS) for the complete official set