feat(client): add create/edit environment pages and hoverable cards

- add CreateEnvironmentPage and EditEnvironmentPage with pre-filled form
- add /environments/new and /environments/:id/edit routes
- add Edit option to card context menu and detail page toolbar
- move env id pill to card footer (left), timestamp stays right
- make env cards clickable (navigate to detail); cog stops propagation
- add hoverable Card variant with primary border+shadow on hover
- add link color tokens and global anchor styles for both themes
- fix Timestamp pill visibility in dark mode with border token
- add DescriptionList truncate prop with ellipsis and title tooltip
- stack DescriptionList dd below dt with 8px gap between items

client/src/pages/Page.module.css

@@ -16,6 +16,12 @@
   margin-bottom: var(--space-4);
 }
 
+.toolbarActions {
+  display: flex;
+  align-items: center;
+  gap: var(--space-2);
+}
+
 .error {
   margin-bottom: var(--space-4);
   padding: var(--space-3) var(--space-4);
@@ -44,6 +50,21 @@
   gap: var(--space-3);
 }
 
+.envCardAdd {
+  display: flex;
+  align-items: center;
+  justify-content: center;
+  min-height: 120px;
+  border: 2px dashed var(--color-border);
+  border-radius: var(--radius-lg);
+  transition: border-color var(--transition), background var(--transition);
+}
+
+.envCardAdd:hover {
+  border-color: var(--color-primary);
+  background: color-mix(in srgb, var(--color-primary) 6%, transparent);
+}
+
 .envCardHeader {
   display: flex;
   align-items: center;
@@ -54,15 +75,21 @@
 .envCardId {
   font-size: var(--font-size-xs);
   font-weight: 700;
-  color: inherit;
+  color: var(--color-text-muted);
   flex-shrink: 0;
-  background: rgba(0, 0, 0, 0.22);
-  border: 1px solid rgba(0, 0, 0, 0.35);
+  border: var(--border-width) solid var(--color-border);
   border-radius: 9999px;
   padding: 1px var(--space-2);
   line-height: 1.6;
 }
 
+.envCardFooter {
+  display: flex;
+  align-items: center;
+  justify-content: space-between;
+  width: 100%;
+}
+
 .envCardHeader button {
   color: inherit;
   padding: var(--space-1);
@@ -115,6 +142,25 @@
   color: var(--color-text-muted);
 }
 
+/* ── Environment form ───────────────────────────────────────────────────── */
+
+.formCard {
+  max-width: 540px;
+}
+
+.formFields {
+  display: flex;
+  flex-direction: column;
+  gap: var(--space-4);
+  margin-bottom: var(--space-6);
+}
+
+.formActions {
+  display: flex;
+  gap: var(--space-3);
+  justify-content: flex-end;
+}
+
 /* ── Environment detail page ────────────────────────────────────────────── */
 
 .detailToolbar {