feat: 新增短剧/媒体生成能力并脱敏数据库脚本

- 新增音频/视频/图片生成服务与 Atlas、OpenAI 实现
- 新增短剧脚本生成、分镜与 ffmpeg 合成模块
- 新增 Coze/Dify 聊天 provider 及 Agent 配置
- 脱敏 SQL 脚本：移除真实 DeepSeek API Key，掩码 COS 桶名
- 清理过期的 SQL update 脚本与 chat 文档

Co-Authored-By: Claude <noreply@anthropic.com>

docs/script/install-ffmpeg-windows.ps1

@@ -0,0 +1,86 @@
+[CmdletBinding()]
+param(
+    [switch]$Force
+)
+
+$ErrorActionPreference = 'Stop'
+
+function Find-Executable([string]$Name) {
+    $command = Get-Command $Name -ErrorAction SilentlyContinue
+    if ($command) {
+        return $command.Source
+    }
+
+    $roots = @(
+        (Join-Path $env:LOCALAPPDATA 'Microsoft\WinGet\Packages'),
+        (Join-Path $env:USERPROFILE 'scoop\apps\ffmpeg'),
+        'C:\ProgramData\chocolatey\bin',
+        'C:\ffmpeg'
+    )
+    foreach ($root in $roots) {
+        if (-not (Test-Path $root)) { continue }
+        $match = Get-ChildItem -Path $root -Filter "$Name.exe" -Recurse -ErrorAction SilentlyContinue |
+            Select-Object -First 1 -ExpandProperty FullName
+        if ($match) { return $match }
+    }
+    return $null
+}
+
+$ffmpeg = Find-Executable 'ffmpeg'
+$ffprobe = Find-Executable 'ffprobe'
+
+if ($Force -or -not $ffmpeg -or -not $ffprobe) {
+    $winget = Get-Command winget -ErrorAction SilentlyContinue
+    if (-not $winget) {
+        throw '未找到 winget。请先从 Microsoft Store 安装“应用安装程序”，或使用项目 Dockerfile 运行后端。'
+    }
+
+    Write-Host '正在通过 winget 安装 FFmpeg...' -ForegroundColor Cyan
+    & winget install --id Gyan.FFmpeg --exact --source winget `
+        --accept-package-agreements --accept-source-agreements
+    if ($LASTEXITCODE -ne 0) {
+        throw "winget 安装失败，退出码: $LASTEXITCODE"
+    }
+
+    $ffmpeg = Find-Executable 'ffmpeg'
+    $ffprobe = Find-Executable 'ffprobe'
+}
+
+if (-not $ffmpeg -or -not $ffprobe) {
+    throw 'FFmpeg 已安装但未能定位 ffmpeg.exe 或 ffprobe.exe。请重新打开 PowerShell 后再次运行脚本。'
+}
+
+$binDirectory = Split-Path -Parent $ffmpeg
+[Environment]::SetEnvironmentVariable('FFMPEG_PATH', $ffmpeg, 'User')
+[Environment]::SetEnvironmentVariable('FFPROBE_PATH', $ffprobe, 'User')
+
+$userPath = [Environment]::GetEnvironmentVariable('Path', 'User')
+$pathParts = @($userPath -split ';' | Where-Object { $_ })
+if ($pathParts -notcontains $binDirectory) {
+    $newPath = (@($pathParts) + $binDirectory) -join ';'
+    [Environment]::SetEnvironmentVariable('Path', $newPath, 'User')
+}
+
+$env:FFMPEG_PATH = $ffmpeg
+$env:FFPROBE_PATH = $ffprobe
+if (($env:Path -split ';') -notcontains $binDirectory) {
+    $env:Path = "$binDirectory;$env:Path"
+}
+
+Write-Host "ffmpeg:  $ffmpeg" -ForegroundColor Green
+Write-Host "ffprobe: $ffprobe" -ForegroundColor Green
+
+& $ffmpeg -hide_banner -version | Select-Object -First 1
+& $ffprobe -hide_banner -version | Select-Object -First 1
+
+$encoders = & $ffmpeg -hide_banner -encoders 2>&1 | Out-String
+if ($encoders -notmatch '\blibx264\b') {
+    throw '当前 FFmpeg 不包含 libx264 编码器，无法满足短剧合成配置。'
+}
+if ($encoders -notmatch '\baac\b') {
+    throw '当前 FFmpeg 不包含 AAC 编码器，无法满足短剧合成配置。'
+}
+
+Write-Host ''
+Write-Host '安装与配置完成。请完全重启 IntelliJ IDEA 和 ruoyi-ai 后端服务。' -ForegroundColor Yellow
+Write-Host '重启后，Spring 将从 FFMPEG_PATH 和 FFPROBE_PATH 读取绝对路径。'