fix: remove manual project creation, smart sequence release, received-invoices schema fix

- Remove ProjectCreate page, POST /projects endpoint, and next-number endpoint
- Projects can only be created through orders (shared numbering sequence)
- Remove dead CreateProjectSchema and createProject service function
- Delete 'order' row from number_sequences (unused; code uses 'shared')
- Smart sequence release: decrement last_number only when deleting the highest number
- Fix received-invoices stats referencing non-existent is_deleted and amount_czk columns
- Update deploy instructions in CLAUDE.md (npm install, prisma migrate deploy)

Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>

src/schemas/projects.schema.ts

@@ -1,35 +1,5 @@
 import { z } from "zod";
 
-const safeProjectNumber = z
-  .string()
-  .regex(/^[\p{L}\p{N}_\-.]+$/u, "Číslo projektu obsahuje nepovolené znaky")
-  .nullish();
-
-export const CreateProjectSchema = z.object({
-  project_number: safeProjectNumber,
-  name: z.string().nullish(),
-  customer_id: z
-    .union([z.number(), z.string()])
-    .transform((v) => Number(v))
-    .nullish(),
-  responsible_user_id: z
-    .union([z.number(), z.string()])
-    .transform((v) => Number(v))
-    .nullish(),
-  quotation_id: z
-    .union([z.number(), z.string()])
-    .transform((v) => Number(v))
-    .nullish(),
-  order_id: z
-    .union([z.number(), z.string()])
-    .transform((v) => Number(v))
-    .nullish(),
-  status: z.string().optional().default("aktivni"),
-  start_date: z.string().nullish(),
-  end_date: z.string().nullish(),
-  notes: z.string().nullish(),
-});
-
 export const UpdateProjectSchema = z.object({
   name: z.string().nullish(),
   status: z.string().optional(),
@@ -58,6 +28,5 @@ export const CreateProjectNoteSchema = z.object({
   content: z.string().nullish(),
 });
 
-export type CreateProjectInput = z.infer<typeof CreateProjectSchema>;
 export type UpdateProjectInput = z.infer<typeof UpdateProjectSchema>;
 export type CreateProjectNoteInput = z.infer<typeof CreateProjectNoteSchema>;