refactor: remove dead code, unused exports and redundant dependencies

- drop dotenv (Node 24 process.loadEnvFile) and dompurify (only used by dead code)
- delete unused ui components/hooks (card, progress, checkbox, use-confirm, use-prompt)
- delete dead sanitizeHtml/sanitizeCss, url-security helpers, patch-resume tool,
  schema/page, createResumePatches, patch-proposal preview builder, fonts fallback helpers
- inline single-caller wrappers (flags service, auth getSession, pdf renderer passthrough)
- deduplicate template color helpers into shared/color-helpers
- unexport 50+ internal-only symbols, remove dead export-map entries
- replace hand-rolled unique()/useIsMobile with Set spread and usehooks-ts

packages/ai/src/resume/sanitize.ts

@@ -4,10 +4,13 @@ import { jsonrepair } from "jsonrepair";
 import { flattenError, ZodError } from "zod";
 import { resumeDataSchema } from "@reactive-resume/schema/resume/data";
 import { defaultResumeData } from "@reactive-resume/schema/resume/default";
-import { isObject } from "@reactive-resume/utils/sanitize";
 import { generateId } from "@reactive-resume/utils/string";
 import { buildAiExtractionTemplate } from "./extraction-template";
 
+function isObject(value: unknown): value is Record<string, unknown> {
+	return typeof value === "object" && value !== null && !Array.isArray(value);
+}
+
 const aiExtractionTemplate = buildAiExtractionTemplate();
 
 type SectionKey = keyof typeof sectionRequiredFieldMap;
@@ -24,13 +27,13 @@ type DroppedSectionItemEntry = {
 	reason: string;
 };
 
-export type ResumeSanitizationDiagnostics = {
+type ResumeSanitizationDiagnostics = {
 	coercions: CoercionEntry[];
 	droppedSectionItems: DroppedSectionItemEntry[];
 	salvageApplied: boolean;
 };
 
-export type ResumeSanitizationResult = {
+type ResumeSanitizationResult = {
 	data: ResumeData;
 	diagnostics: ResumeSanitizationDiagnostics;
 };