[Tracking] CDN: resolve TODOs

Generated at commit 57827bc9:

• src/cdn/routes/icons.ts:28: // TODO: check premium and animated pfp are allowed in the config
• src/cdn/routes/icons.ts:29: // TODO: generate different sizes of icon
• src/cdn/routes/icons.ts:30: // TODO: generate different image types of icon
• src/cdn/routes/icons.ts:31: // TODO: delete old icons
• src/cdn/routes/guild-profiles.ts:28: // TODO: check premium and animated pfp are allowed in the config
• src/cdn/routes/guild-profiles.ts:29: // TODO: generate different sizes of icon
• src/cdn/routes/guild-profiles.ts:30: // TODO: generate different image types of icon
• src/cdn/routes/guild-profiles.ts:31: // TODO: delete old icons
• src/cdn/routes/emojis.ts:28: // TODO: check premium and animated pfp are allowed in the config
• src/cdn/routes/emojis.ts:29: // TODO: generate different sizes of icon
• src/cdn/routes/emojis.ts:30: // TODO: generate different image types of icon
• src/cdn/routes/emojis.ts:31: // TODO: delete old icons
• src/cdn/routes/discovery-splashes.ts:28: // TODO: check premium and animated pfp are allowed in the config
• src/cdn/routes/discovery-splashes.ts:29: // TODO: generate different sizes of icon
• src/cdn/routes/discovery-splashes.ts:30: // TODO: generate different image types of icon
• src/cdn/routes/discovery-splashes.ts:31: // TODO: delete old icons
• src/cdn/routes/stickers.ts:28: // TODO: check premium and animated pfp are allowed in the config
• src/cdn/routes/stickers.ts:29: // TODO: generate different sizes of icon
• src/cdn/routes/stickers.ts:30: // TODO: generate different image types of icon
• src/cdn/routes/stickers.ts:31: // TODO: delete old icons
• src/cdn/routes/team-icons.ts:28: // TODO: check premium and animated pfp are allowed in the config
• src/cdn/routes/team-icons.ts:29: // TODO: generate different sizes of icon
• src/cdn/routes/team-icons.ts:30: // TODO: generate different image types of icon
• src/cdn/routes/team-icons.ts:31: // TODO: delete old icons
• src/cdn/routes/app-icons.ts:28: // TODO: check premium and animated pfp are allowed in the config
• src/cdn/routes/app-icons.ts:29: // TODO: generate different sizes of icon
• src/cdn/routes/app-icons.ts:30: // TODO: generate different image types of icon
• src/cdn/routes/app-icons.ts:31: // TODO: delete old icons
• src/cdn/routes/role-icons.ts:30: // TODO: check user rights and perks and animated pfp are allowed in the policies
• src/cdn/routes/role-icons.ts:31: // TODO: generate different sizes of icon
• src/cdn/routes/role-icons.ts:32: // TODO: generate different image types of icon
• src/cdn/routes/banners.ts:28: // TODO: check premium and animated pfp are allowed in the config
• src/cdn/routes/banners.ts:29: // TODO: generate different sizes of icon
• src/cdn/routes/banners.ts:30: // TODO: generate different image types of icon
• src/cdn/routes/banners.ts:31: // TODO: delete old icons
• src/cdn/routes/splashes.ts:28: // TODO: check premium and animated pfp are allowed in the config
• src/cdn/routes/splashes.ts:29: // TODO: generate different sizes of icon
• src/cdn/routes/splashes.ts:30: // TODO: generate different image types of icon
• src/cdn/routes/splashes.ts:31: // TODO: delete old icons
• src/cdn/routes/app-assets.ts:28: // TODO: check premium and animated pfp are allowed in the config
• src/cdn/routes/app-assets.ts:29: // TODO: generate different sizes of icon
• src/cdn/routes/app-assets.ts:30: // TODO: generate different image types of icon
• src/cdn/routes/app-assets.ts:31: // TODO: delete old icons
• src/cdn/routes/channel-icons.ts:28: // TODO: check premium and animated pfp are allowed in the config
• src/cdn/routes/channel-icons.ts:29: // TODO: generate different sizes of icon
• src/cdn/routes/channel-icons.ts:30: // TODO: generate different image types of icon
• src/cdn/routes/channel-icons.ts:31: // TODO: delete old icons
• src/cdn/routes/discover-splashes.ts:28: // TODO: check premium and animated pfp are allowed in the config
• src/cdn/routes/discover-splashes.ts:29: // TODO: generate different sizes of icon
• src/cdn/routes/discover-splashes.ts:30: // TODO: generate different image types of icon
• src/cdn/routes/discover-splashes.ts:31: // TODO: delete old icons
• src/cdn/routes/avatars.ts:28: // TODO: check premium and animated pfp are allowed in the config
• src/cdn/routes/avatars.ts:29: // TODO: generate different sizes of icon
• src/cdn/routes/avatars.ts:30: // TODO: generate different image types of icon
• src/cdn/routes/avatars.ts:31: // TODO: delete old icons
• src/cdn/util/FileStorage.ts:26: // TODO: split stored files into separate folders named after cloned route
• src/cdn/util/FileStorage.ts:77: //TODO we should delete the parent directory if empty
• src/cdn/util/Storage.ts:44: // TODO: move this to some start func, so it doesn't run when server is imported
• src/cdn/util/S3Storage.ts:63: // TODO: does this even work?
• src/cdn/util/basicCrdFileRouter.ts:27: // TODO: check premium and animated pfp are allowed in the config
• src/cdn/util/basicCrdFileRouter.ts:28: // TODO: generate different sizes of icon
• src/cdn/util/basicCrdFileRouter.ts:29: // TODO: generate different image types of icon
• src/cdn/util/basicCrdFileRouter.ts:30: // TODO: delete old icons

Start by reviewing the unchecked TODOs across src/cdn/routes/*.ts and the listed files in src/cdn/util/, especially basicCrdFileRouter.ts, FileStorage.ts, Storage.ts, and S3Storage.ts. Determine the intended behavior for permissions, image variants, cleanup, initialization, and S3 storage before splitting the tracking issue into focused changes; done means the relevant TODOs are resolved.