feat(icons): add square-text (#4609)

* feat(icons): add square-text

Adds square-text: a solid square containing three ragged lines of text.

The set has square-dashed-text but no solid-border equivalent, which is
the same asymmetry solid/dashed pairs elsewhere avoid. This reuses
square-dashed-text's exact text glyph (M7 8h8 / M7 12h10 / M7 16h6) on the
standard 18x18 rx=2 square, so it reads as the solid twin.

Distinct from square-menu, whose lines are equal full-width (a menu, not
running text).

* chore(icons): expand square-text tags and fill use-cases

Applies the metadata bot's tag suggestions (curated) and fills the
use-cases field.

* chore(icons): promote lab/text-square to square-text

Per review on #4609: square-text is identical to lab/text-square, so
this removes the lab entry and merges its metadata (tags + development
category) into the promoted icon.

* chore(icons): credit danielbayley and expand square-text use-cases

Per review on #4609: adds @danielbayley (original author of lab/text-square)
to contributors, and expands use-cases per @ericfennis.

icons/square-text.json

@@ -0,0 +1,42 @@
+{
+  "$schema": "../icon.schema.json",
+  "contributors": [
+    "danielbayley",
+    "samuelalake"
+  ],
+  "use-cases": [
+    "representing a text block or content card",
+    "indicating a document, article, or post",
+    "using as a placeholder for text content in a layout",
+    "labeling a notes or memo feature",
+    "denoting a text-only module or widget in a dashboard"
+  ],
+  "tags": [
+    "text",
+    "paragraph",
+    "content",
+    "note",
+    "document",
+    "body",
+    "copy",
+    "article",
+    "square",
+    "container",
+    "block",
+    "card",
+    "placeholder",
+    "log",
+    "page",
+    "paper",
+    "sheet",
+    "list",
+    "script",
+    "code",
+    "editor"
+  ],
+  "categories": [
+    "text",
+    "shapes",
+    "development"
+  ]
+}

icons/square-text.svg

@@ -10,7 +10,7 @@
   stroke-linejoin="round"
 >
   <rect width="18" height="18" x="3" y="3" rx="2" />
+  <path d="M7 8h8" />
   <path d="M7 12h10" />
   <path d="M7 16h6" />
-  <path d="M7 8h8" />
 </svg>

lab/text-square.json

@@ -1,19 +0,0 @@
-{
-  "$schema": "../icon.schema.json",
-  "tags": [
-    "note",
-    "log",
-    "document",
-    "page",
-    "paper",
-    "sheet",
-    "list",
-    "script",
-    "code",
-    "editor"
-  ],
-  "categories": [
-    "text",
-    "development"
-  ]
-}