refactor!: rename oo-cli → oo, split library by domain, relocate applications

BREAKING:
- Binary renamed oo-cli → oo; install path is now
  github.com/eslider/go-onlyoffice/cmd/oo.
- Former internal/cli tree removed; cobra commands live in cmd/oo/ as
  package main, split by domain (calendar.go, crm.go, tasks.go, apps.go,
  common.go, main.go).
- internal/applications moved to cmd/oo/applications/ (CV-specific workflow;
  not a library feature).
- examples/applications removed (it depended on an internal package).

Library split (mechanical, zero API surface change):
- client.go  — Client, Credentials, Defaults, env helpers, NewClient.
- request.go — Request, Query, Time, Token, MetaResponse, Permissions.
- auth.go    — Authenticate/AuthenticateContext/InvalidateToken.
- http.go    — transport + ResponseArray/ResponseObject/postFormObject/
               putFormObject/deleteObject/unmarshalResponseObject (renamed
               from httpx.go).
- projects.go, tasks.go, users.go, calendar.go, crm.go, files.go — typed
  / untyped domain methods. tasks_extra.go merged into tasks.go.
- onlyoffice.go deleted (content redistributed).

AGENTS.md, CHANGELOG.md, README.md updated accordingly.

Made-with: Cursor

cmd/oo/main.go

@@ -0,0 +1,24 @@
+// Command oo is a thin CLI over the github.com/eslider/go-onlyoffice library.
+// It exposes calendar, CRM, tasks, subtasks, and application-sync commands.
+//
+// Build & install:
+//
+//	go install github.com/eslider/go-onlyoffice/cmd/oo@latest
+//
+// Rationale: previous versions shipped as `oo-cli` with the cobra tree living
+// in `internal/cli`. Since the CLI is a consumer of the library — not a part
+// of its public surface — cobra lives right here in package main, split by
+// domain (calendar.go, crm.go, tasks.go, apps.go).
+package main
+
+import (
+	"fmt"
+	"os"
+)
+
+func main() {
+	if err := execute(); err != nil {
+		fmt.Fprintln(os.Stderr, err)
+		os.Exit(1)
+	}
+}