Show the portion of the console working directory that we can (#13724)

A quick change to show the portion of the working directory in the
console that we can, instead of letting it disappear when the console is
narrow or the directory name is long. You can hover to see the whole
thing.

<img width="525" height="350" alt="image"
src="https://github.com/user-attachments/assets/8b7d692c-fb1e-459c-b3de-939e4672ddfa"
/>

This is a pretty simple approach; it might be interesting to collapse
_portions_ of the paths so you can see e.g. the beginning and ending
segments, but want to keep this simple for now.

Fixes #12772.

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#### New Features

- N/A

#### Bug Fixes

- Fix issue causing working directory to disappear in Console tab when
it is long or console is narrow (#12772).


### Validation Steps

1. Change to a directory that has a long name
2. Shrink the Console
3. Hover over the truncated text

Author: jmcphers

src/vs/platform/positronActionBar/browser/positronDynamicActionBar.tsx

@@ -77,6 +77,13 @@ export interface DynamicActionBarAction {
 	 * should appear as a submenu in the overflow menu.
 	 */
 	overflowContextMenuSubmenu?: OverflowContextMenuSubmenu;
+
+	/**
+	 * When true, the action shrinks to fit the available space instead of
+	 * being dropped from the layout. The action's component is responsible for
+	 * truncating its content (e.g. via CSS text-overflow: ellipsis).
+	 */
+	growable?: boolean;
 }
 
 /**
@@ -301,6 +308,16 @@ export const PositronDynamicActionBar = (props: PositronDynamicActionBarProps) =
 
 				// Handle overflowing.
 				if (separatorWidth + width > layoutWidth) {
+					// Growable actions shrink to fill remaining space instead of being dropped,
+					// as long as the fixed width still fits. The component handles truncation.
+					if (action.growable && action.fixedWidth + separatorWidth <= layoutWidth) {
+						width = layoutWidth - separatorWidth;
+						gridEntries.push({ width, action });
+						layoutWidth = 0;
+						overflowing = true;
+						overflowActions.push(...actions.slice(i + 1).filter(hasOverflowEntry));
+						return;
+					}
 					overflowing = true;
 					overflowActions.push(...actions.slice(i).filter(hasOverflowEntry));
 					return;

src/vs/workbench/contrib/positronConsole/browser/components/actionBar.tsx

@@ -366,6 +366,7 @@ export const ActionBar = (props: ActionBarProps) => {
 			fixedWidth: DEFAULT_ACTION_BAR_BUTTON_WIDTH,
 			text: directoryLabel,
 			separator: false,
+			growable: true,
 			component: <CurrentWorkingDirectory directoryLabel={directoryLabel} />
 		}
 	];

src/vs/workbench/contrib/positronConsole/browser/components/currentWorkingDirectory.css

@@ -5,6 +5,8 @@
 
 .current-working-directory-label {
 	display: flex;
+	width: 100%;
+	min-width: 0;
 	font-size: 12px;
 	overflow: hidden;
 	align-items: center;
@@ -13,10 +15,12 @@
 
 .current-working-directory-label .codicon {
 	padding-top: 1px;
+	flex-shrink: 0;
 	color: var(--vscode-positronActionBar-foreground);
 }
 
 .current-working-directory-label .label {
+	min-width: 0;
 	overflow: hidden;
 	padding-left: 5px;
 	white-space: nowrap;