Many UX and correctness improvements

- Components URL reflects selected component (/components/:id), survives refresh
- Word-split search: "0603 res" matches "Resistor 0603"
- Left pane resizable with localStorage persistence
- Field values rendered via central render_field_value() (units, URLs, extensible)
- Fields sorted alphabetically in both detail view and edit dialog
- Edit component dialog widened; field rows use shared grid columns (table-like)
- No space between value and unit (supports prefix suffixes like k, M, µ)
- Grid viewer highlights and scrolls to cell when navigating from component detail
- Cell inventory overlay items are <a> tags — middle-click opens in new tab
- PDF files stored with sanitized human-readable filename, not random ID
- PDF rename also renames file on disk
- Atomic rename via renameat2(RENAME_NOREPLACE) through tools/mv-sync
- Fix .cell-thumb-link → .cell-thumb-preview (div, not anchor), cursor: zoom-in
- Fix field name overflow in detail view (auto column width, overflow-wrap)
- Fix link color: use --accent instead of browser default dark blue

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

tools/mv-sync.c

@@ -0,0 +1,42 @@
+/*
+ * mv-sync: atomic rename that fails if the destination already exists.
+ *
+ * Uses renameat2(2) with RENAME_NOREPLACE (Linux 3.15+).
+ *
+ * Exit codes:
+ *   0  success
+ *   1  rename failed (reason on stderr)
+ *   2  wrong number of arguments
+ */
+
+#define _GNU_SOURCE
+#include <errno.h>
+#include <fcntl.h>
+#include <stdio.h>
+#include <string.h>
+#include <unistd.h>
+#include <sys/syscall.h>
+
+#ifndef RENAME_NOREPLACE
+#define RENAME_NOREPLACE (1 << 0)
+#endif
+
+int main(int argc, char *argv[]) {
+	if (argc != 3) {
+		fprintf(stderr, "usage: mv-sync <src> <dst>\n");
+		return 2;
+	}
+
+	long ret = syscall(SYS_renameat2,
+		AT_FDCWD, argv[1],
+		AT_FDCWD, argv[2],
+		RENAME_NOREPLACE);
+
+	if (ret != 0) {
+		fprintf(stderr, "mv-sync: rename \"%s\" -> \"%s\": %s\n",
+			argv[1], argv[2], strerror(errno));
+		return 1;
+	}
+
+	return 0;
+}