feat!: Make everything ISelectable focusable (#9004)

* feat!: Make bubbles, comments, and icons focusable

* feat!: Make ISelectable and ICopyable focusable.

* feat: Consolidate selection calls.

Now everything is based on focus with selection only being used as a
proxy.

* feat: Invert responsibility for setSelected().

Now setSelected() is only for quasi-external use.

* feat: Push up shadow check to getters.

Needed new common-level helper.

* chore: Lint fixes.

* feat!: Allow IFocusableNode to disable focus.

* chore: post-merge lint fixes

* fix: Fix tests + text bubble focusing.

This fixed then regressed a circular dependency causing the node and
advanced compilation steps to fail. This investigation is ongoing.

* fix: Clean up & fix imports.

This ensures the node and advanced compilation test steps now pass.

* fix: Lint fixes + revert commented out logic.

* chore: Remove unnecessary cast.

Addresses reviewer comment.

* fix: Some issues and a bunch of clean-ups.

This addresses a bunch of review comments, and fixes selecting workspace
comments.

* chore: Lint fix.

* fix: Remove unnecessary shadow consideration.

* chore: Revert import.

* chore: Some doc updates & added a warn statement.

core/keyboard_nav/line_cursor.ts

@@ -14,7 +14,6 @@
  */
 
 import {BlockSvg} from '../block_svg.js';
-import * as common from '../common.js';
 import {ConnectionType} from '../connection_type.js';
 import {Field} from '../field.js';
 import {FieldCheckbox} from '../field_checkbox.js';
@@ -561,12 +560,7 @@ export class LineCursor extends Marker {
    * @returns The current field, connection, or block the cursor is on.
    */
   override getCurNode(): INavigable<any> | null {
-    if (!this.updateCurNodeFromFocus()) {
-      // Fall back to selection if focus fails to sync. This can happen for
-      // non-focusable nodes or for cases when focus may not properly propagate
-      // (such as for mouse clicks).
-      this.updateCurNodeFromSelection();
-    }
+    this.updateCurNodeFromFocus();
     return super.getCurNode();
   }
 
@@ -593,60 +587,18 @@ export class LineCursor extends Marker {
     }
   }
 
-  /**
-   * Updates the current node to match the selection.
-   *
-   * Clears the current node if it's on a block but the selection is null.
-   * Sets the node to a block if selected for our workspace.
-   * For shadow blocks selections the parent is used by default (unless we're
-   * already on the shadow block via keyboard) as that's where the visual
-   * selection is.
-   */
-  private updateCurNodeFromSelection() {
-    const curNode = super.getCurNode();
-    const selected = common.getSelected();
-
-    if (selected === null && curNode instanceof BlockSvg) {
-      this.setCurNode(null);
-      return;
-    }
-    if (selected?.workspace !== this.workspace) {
-      return;
-    }
-    if (selected instanceof BlockSvg) {
-      let block: BlockSvg | null = selected;
-      if (selected.isShadow()) {
-        // OK if the current node is on the parent OR the shadow block.
-        // The former happens for clicks, the latter for keyboard nav.
-        if (curNode && (curNode === block || curNode === block.getParent())) {
-          return;
-        }
-        block = block.getParent();
-      }
-      if (block) {
-        this.setCurNode(block);
-      }
-    }
-  }
-
   /**
    * Updates the current node to match what's currently focused.
-   *
-   * @returns Whether the current node has been set successfully from the
-   *     current focused node.
    */
-  private updateCurNodeFromFocus(): boolean {
+  private updateCurNodeFromFocus() {
     const focused = getFocusManager().getFocusedNode();
 
     if (focused instanceof BlockSvg) {
       const block: BlockSvg | null = focused;
       if (block && block.workspace === this.workspace) {
         this.setCurNode(block);
-        return true;
       }
     }
-
-    return false;
   }
 
   /**