feat(editor): add WMVC (Movie Credits Roll) — 112th open format

Novel replacement for the embedded credit-roll text
vanilla WoW carried inside the cinematic-renderer blob
(the post-cinematic credits that scroll up the screen
after each expansion intro). Each entry binds one
credits category (Production / Music / Voice Acting /
etc.) for one cinematic to its ordered list of credit
lines.

First catalog with a variable-length STRING array
payload — previous variable-length formats used int
arrays (WCMR waypoints / WCMG mutex spells / WPTT
rank-spells / WBAB rank chains / WRPR unlocked items +
recipes). The lines[] field serializes as count +
(length + bytes)* per line, mirroring how strings work
elsewhere in the catalog set just lifted into a per-
entry array.

Seven category enum values cover the full credit
taxonomy: Production / Music / Audio / Engineering /
Art / Voice / Special. Three preset emitters:
makeWotLKIntro (5 blocks for the WotLK Arthas/Terenas
cinematic with the actual canonical music credits —
Brower/Duke/Stafford/Hayes), makeQuestCinema (3-block
template for per-quest cinematics), makeStarterRoll
(4-block generic template).

orderHint sorts blocks within a single cinematic so
the renderer can render Production -> Direction ->
Music -> Voice -> Special Thanks in canonical order
without depending on entry order in the binary.

Validator's most novel checks combine string + grouping
constraints unique to credit rolls: per-cinematic
orderHint slot uniqueness — two blocks at the same
(cinematicId, orderHint) would render in non-
deterministic order due to the std::sort being stable
but content-order undefined. Per-line: empty lines
warn (would render as blank, intentional spacers
should use a placeholder character), lines >80 chars
warn (text-buffer wrap at the canonical 80-char
credit-renderer width).

Format count 111 -> 112. CLI flag count 1206 -> 1211.

include/pipeline/wowee_movie_credits.hpp

@@ -0,0 +1,122 @@
+#pragma once
+
+#include <cstdint>
+#include <string>
+#include <vector>
+
+namespace wowee {
+namespace pipeline {
+
+// Wowee Open Movie Credits Roll catalog (.wmvc) —
+// novel replacement for the embedded credit-roll text
+// vanilla WoW carried inside the cinematic-renderer
+// blob (the post-cinematic credits that scroll up the
+// screen after each expansion intro). Each entry binds
+// one credits category (Production / Music / Voice
+// Acting / etc.) for one cinematic to its ordered list
+// of credit lines.
+//
+// First catalog with a variable-length STRING array
+// payload — previous variable-length formats used int
+// arrays (WCMR waypoints, WCMG members, WPTT spell
+// rank-arrays, WBAB rank chains, WRPR unlocked items
+// + recipes). The lines[] field is serialized as
+// count + (length + bytes)* per line.
+//
+// Cross-references with previously-added formats:
+//   WCMS: cinematicId references the WCMS cinematic
+//         catalog (the cinematic these credits play
+//         after).
+//
+// Binary layout (little-endian):
+//   magic[4]            = "WMVC"
+//   version (uint32)    = current 1
+//   nameLen + name (catalog label)
+//   entryCount (uint32)
+//   entries (each):
+//     rollId (uint32)
+//     nameLen + name
+//     descLen + description
+//     cinematicId (uint32)
+//     category (uint8)            — Production / Music /
+//                                    Audio / Engineering
+//                                    / Art / Voice /
+//                                    Special
+//     pad0 / pad1 / pad2 (uint8)
+//     orderHint (uint16)          — sort key for the
+//                                    cinematic's credit
+//                                    order (lower =
+//                                    earlier in roll)
+//     pad4 / pad5 (uint8)
+//     iconColorRGBA (uint32)
+//     lineCount (uint32)
+//     lines (count × { uint32 strLen + bytes })
+struct WoweeMovieCredits {
+    enum Category : uint8_t {
+        Production  = 0,    // Director, Producer, etc.
+        Music       = 1,    // Composer, Orchestra
+        Audio       = 2,    // Sound Design, Foley
+        Engineering = 3,    // Tools, Pipeline
+        Art         = 4,    // Concept, Modeling, Anim
+        Voice       = 5,    // Voice cast
+        Special     = 6,    // Special Thanks, Dedication
+    };
+
+    struct Entry {
+        uint32_t rollId = 0;
+        std::string name;
+        std::string description;
+        uint32_t cinematicId = 0;
+        uint8_t category = Production;
+        uint8_t pad0 = 0;
+        uint8_t pad1 = 0;
+        uint8_t pad2 = 0;
+        uint16_t orderHint = 0;
+        uint8_t pad4 = 0;
+        uint8_t pad5 = 0;
+        uint32_t iconColorRGBA = 0xFFFFFFFFu;
+        std::vector<std::string> lines;
+    };
+
+    std::string name;
+    std::vector<Entry> entries;
+
+    bool isValid() const { return !entries.empty(); }
+
+    const Entry* findById(uint32_t rollId) const;
+
+    // Returns all credit-roll entries for one cinematic,
+    // sorted by orderHint. Used by the credit renderer
+    // to assemble the full scroll for one cinematic.
+    std::vector<const Entry*> findByCinematic(uint32_t cinematicId) const;
+};
+
+class WoweeMovieCreditsLoader {
+public:
+    static bool save(const WoweeMovieCredits& cat,
+                     const std::string& basePath);
+    static WoweeMovieCredits load(const std::string& basePath);
+    static bool exists(const std::string& basePath);
+
+    // Preset emitters used by --gen-mvc* variants.
+    //
+    //   makeWotLKIntro    — 5 categories for the WotLK
+    //                        cinematic (Production /
+    //                        Direction / Music / Voice
+    //                        Acting / Special Thanks)
+    //                        with 3-4 lines each.
+    //   makeQuestCinema   — 3 categories for a typical
+    //                        per-quest cinematic (Quest
+    //                        Designer / Voice Cast /
+    //                        Cinematic Director).
+    //   makeStarterRoll   — 4 categories demonstrating
+    //                        roll structure (Production
+    //                        / Engineering / Art /
+    //                        Special Thanks).
+    static WoweeMovieCredits makeWotLKIntro(const std::string& catalogName);
+    static WoweeMovieCredits makeQuestCinema(const std::string& catalogName);
+    static WoweeMovieCredits makeStarterRoll(const std::string& catalogName);
+};
+
+} // namespace pipeline
+} // namespace wowee