Redesign and clean up all icons across Zed (#35856)

- [x] Clean up unused and old icons
- [x] Swap SVG for all in-use icons with the redesigned version
- [x] Document guidelines

Release Notes:

- N/A

crates/icons/README.md

@@ -0,0 +1,29 @@
+# Zed Icons
+
+## Guidelines
+
+Icons are a big part of Zed, and they're how we convey hundreds of actions without relying on labeled buttons.
+When introducing a new icon to the set, it's important to ensure it is consistent with the whole set, which follows a few guidelines:
+
+1. The SVG view box should be 16x16.
+2. For outlined icons, use a 1.5px stroke width.
+3. Not all icons are mathematically aligned; there's quite a bit of optical adjustment. But try to keep the icon within an internal 12x12 bounding box as much as possible while ensuring proper visibility.
+4. Use the `filled` and `outlined` terminology when introducing icons that will have the two variants.
+5. Icons that are deeply contextual may have the feature context as their name prefix. For example, `ToolWeb`, `ReplPlay`, `DebugStepInto`, etc.
+6. Avoid complex layer structure in the icon SVG, like clipping masks and whatnot. When the shape ends up too complex, we recommend running the SVG in [SVGOMG](https://jakearchibald.github.io/svgomg/) to clean it up a bit.
+
+## Sourcing
+
+Most icons are created by sourcing them from [Lucide](https://lucide.dev/).
+Then, they're modified, adjusted, cleaned up, and simplified depending on their use and overall fit with Zed.
+
+Sometimes, we may use other sources like [Phosphor](https://phosphoricons.com/), but we also design many of them completely from scratch.
+
+## Contributing
+
+To introduce a new icon, add the `.svg` file in the `assets/icon` directory and then add its corresponding item in the `icons.rs` file within the `crates` directory.
+
+- SVG files in the assets folder follow a snake case name format.
+- Icons in the `icons.rs` file follow the pascal case name format.
+
+Ensure you tag a member of Zed's design team so we can adjust and double-check any newly introduced icon.

crates/icons/src/icons.rs

@@ -28,16 +28,12 @@ pub enum IconName {
     ArrowCircle,
     ArrowDown,
     ArrowDown10,
-    ArrowDownFromLine,
     ArrowDownRight,
     ArrowLeft,
     ArrowRight,
     ArrowRightLeft,
     ArrowUp,
-    ArrowUpAlt,
-    ArrowUpFromLine,
     ArrowUpRight,
-    ArrowUpRightAlt,
     AudioOff,
     AudioOn,
     Backspace,
@@ -51,28 +47,22 @@ pub enum IconName {
     BoltFilled,
     Book,
     BookCopy,
-    BugOff,
     CaseSensitive,
     Chat,
     Check,
     CheckDouble,
     ChevronDown,
-    /// This chevron indicates a popover menu.
-    ChevronDownSmall,
     ChevronLeft,
     ChevronRight,
     ChevronUp,
     ChevronUpDown,
     Circle,
-    CircleOff,
     CircleHelp,
     Close,
-    Cloud,
     CloudDownload,
     Code,
     Cog,
     Command,
-    Context,
     Control,
     Copilot,
     CopilotDisabled,
@@ -93,16 +83,12 @@ pub enum IconName {
     DebugIgnoreBreakpoints,
     DebugLogBreakpoint,
     DebugPause,
-    DebugRestart,
     DebugStepBack,
     DebugStepInto,
     DebugStepOut,
     DebugStepOver,
-    DebugStop,
-    Delete,
     Diff,
     Disconnected,
-    DocumentText,
     Download,
     EditorAtom,
     EditorCursor,
@@ -113,59 +99,50 @@ pub enum IconName {
     Ellipsis,
     EllipsisVertical,
     Envelope,
-    Equal,
     Eraser,
     Escape,
     Exit,
     ExpandDown,
     ExpandUp,
     ExpandVertical,
-    ExternalLink,
     Eye,
     File,
     FileCode,
-    FileCreate,
     FileDiff,
     FileDoc,
     FileGeneric,
     FileGit,
     FileLock,
+    FileMarkdown,
     FileRust,
-    FileSearch,
-    FileText,
+    FileTextFilled,
+    FileTextOutlined,
     FileToml,
     FileTree,
     Filter,
     Flame,
     Folder,
     FolderOpen,
-    FolderX,
+    FolderSearch,
     Font,
     FontSize,
     FontWeight,
     ForwardArrow,
-    Function,
     GenericClose,
     GenericMaximize,
     GenericMinimize,
     GenericRestore,
     GitBranch,
-    GitBranchSmall,
+    GitBranchAlt,
     Github,
-    Globe,
-    Hammer,
     Hash,
     HistoryRerun,
     Image,
     Indicator,
     Info,
-    InlayHint,
     Keyboard,
-    Layout,
     Library,
-    LightBulb,
     LineHeight,
-    Link,
     ListCollapse,
     ListTodo,
     ListTree,
@@ -173,35 +150,28 @@ pub enum IconName {
     LoadCircle,
     LocationEdit,
     LockOutlined,
-    LspDebug,
-    LspRestart,
-    LspStop,
     MagnifyingGlass,
-    MailOpen,
     Maximize,
     Menu,
     MenuAlt,
     Mic,
     MicMute,
     Minimize,
+    Notepad,
     Option,
     PageDown,
     PageUp,
-    PanelLeft,
-    PanelRight,
     Pencil,
     Person,
-    PersonCircle,
-    PhoneIncoming,
     Pin,
     PlayOutlined,
     PlayFilled,
     Plus,
-    PocketKnife,
     Power,
     Public,
     PullRequest,
     Quote,
+    Reader,
     RefreshTitle,
     Regex,
     ReplNeutral,
@@ -213,28 +183,18 @@ pub enum IconName {
     Return,
     RotateCcw,
     RotateCw,
-    Route,
-    Save,
     Scissors,
     Screen,
-    ScrollText,
-    SearchSelection,
     SelectAll,
     Send,
     Server,
     Settings,
-    SettingsAlt,
     ShieldCheck,
     Shift,
     Slash,
-    SlashSquare,
     Sliders,
-    SlidersVertical,
-    Snip,
     Space,
     Sparkle,
-    SparkleAlt,
-    SparkleFilled,
     Split,
     SplitAlt,
     SquareDot,
@@ -243,7 +203,6 @@ pub enum IconName {
     Star,
     StarFilled,
     Stop,
-    StopFilled,
     Supermaven,
     SupermavenDisabled,
     SupermavenError,
@@ -279,18 +238,13 @@ pub enum IconName {
     TriangleRight,
     Undo,
     Unpin,
-    Update,
     UserCheck,
     UserGroup,
     UserRoundPen,
-    Visible,
-    Wand,
     Warning,
     WholeWord,
-    X,
     XCircle,
     ZedAssistant,
-    ZedAssistantFilled,
     ZedBurnMode,
     ZedBurnModeOn,
     ZedMcpCustom,