Add text tool with rich editor (#54)

* feat: add text tool with rich editor

* Fix text tool interactions and editing flow

* Fix text metadata on destructive erase ops

* Fix rect-select disappearing text after erase

* Finalize text editability on first draw

Author: Microck

celstomp/css/components/overlays.css

@@ -127,6 +127,124 @@
   line-height: 1.35;
 }
 
+.canvasTextEntry {
+  position: fixed;
+  inset: 0;
+  display: none;
+  align-items: center;
+  justify-content: center;
+  background: rgba(0, 0, 0, 0.32);
+  z-index: 9400;
+}
+
+.canvasTextEntry.open {
+  display: flex;
+}
+
+.canvasTextEntryCard {
+  width: min(420px, calc(100vw - 24px));
+  border: 1px solid rgba(255, 255, 255, 0.16);
+  background: rgba(16, 20, 28, 0.96);
+  border-radius: 10px;
+  box-shadow: 0 16px 42px rgba(0, 0, 0, 0.45);
+  padding: 12px;
+  display: grid;
+  gap: 10px;
+}
+
+.canvasTextEntryLabel {
+  font-size: 12px;
+  color: #c7d0db;
+  letter-spacing: 0.04em;
+  text-transform: uppercase;
+}
+
+.canvasTextEntryInput {
+  width: 100%;
+  min-height: 36px;
+  border: 1px solid rgba(255, 255, 255, 0.14);
+  background: rgba(0, 0, 0, 0.28);
+  color: #e2e8f0;
+  border-radius: 8px;
+  padding: 8px 10px;
+}
+
+.canvasTextEntryInput:focus {
+  outline: none;
+  border-color: rgba(92, 179, 255, 0.8);
+  box-shadow: 0 0 0 2px rgba(92, 179, 255, 0.2);
+}
+
+.canvasTextEntryOptions {
+  display: grid;
+  grid-template-columns: repeat(2, minmax(0, 1fr));
+  gap: 8px;
+}
+
+.canvasTextEntryOpt {
+  display: grid;
+  gap: 4px;
+}
+
+.canvasTextEntryOpt > span {
+  font-size: 11px;
+  color: #b7c3d2;
+  letter-spacing: 0.03em;
+}
+
+.canvasTextEntrySelect,
+.canvasTextEntryNum {
+  width: 100%;
+  min-height: 32px;
+  border: 1px solid rgba(255, 255, 255, 0.14);
+  background: rgba(0, 0, 0, 0.28);
+  color: #e2e8f0;
+  border-radius: 8px;
+  padding: 6px 8px;
+}
+
+.canvasTextEntrySelect:focus,
+.canvasTextEntryNum:focus {
+  outline: none;
+  border-color: rgba(92, 179, 255, 0.8);
+  box-shadow: 0 0 0 2px rgba(92, 179, 255, 0.2);
+}
+
+.canvasTextEntryOptCheck {
+  align-items: center;
+  grid-template-columns: auto 1fr;
+  gap: 8px;
+  border: 1px solid rgba(255, 255, 255, 0.12);
+  border-radius: 8px;
+  background: rgba(255, 255, 255, 0.04);
+  padding: 6px 8px;
+}
+
+.canvasTextEntryOptCheck input {
+  margin: 0;
+}
+
+.canvasTextEntryActions {
+  display: flex;
+  justify-content: flex-end;
+  gap: 8px;
+}
+
+.canvasTextEntryBtn {
+  min-height: 34px;
+  padding: 0 12px;
+  border-radius: 8px;
+  border: 1px solid rgba(255, 255, 255, 0.14);
+  background: rgba(255, 255, 255, 0.06);
+  color: #d0d8e2;
+}
+
+.canvasTextEntryBtnPrimary {
+  border-color: rgba(92, 179, 255, 0.6);
+  background: rgba(92, 179, 255, 0.18);
+  color: #9fd5ff;
+}
+
 /* Modal Card */
 .modalBackdrop{
   position: fixed;