Add side panels, task selection, graph animation, and project docs

- Foldable left panel (user profile) and right panel (task details)
- Clicking a task in the list or graph node selects it and shows details
- Both views (task list + graph) always mounted via absolute inset-0 for
  correct canvas dimensions; tabs toggle visibility with opacity
- Graph node selection animation: other nodes repel outward (charge -600),
  then selected node smoothly slides to center (500ms cubic ease-out),
  then charge restores to -120 and graph stabilizes
- Graph re-fits on tab switch and panel resize via ResizeObserver
- Fix UUID string IDs throughout (backend returns UUIDs, not integers)
- Add TaskDetailPanel, UserPanel components
- Add CLAUDE.md project documentation

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

backend/target/debug/build/proc-macro2-cdc80bb011340cc8/invoked.timestamp

@@ -0,0 +1 @@
+This file has an mtime of when this was started.

backend/target/debug/build/proc-macro2-cdc80bb011340cc8/output

@@ -0,0 +1,23 @@
+cargo:rustc-check-cfg=cfg(fuzzing)
+cargo:rustc-check-cfg=cfg(no_is_available)
+cargo:rustc-check-cfg=cfg(no_literal_byte_character)
+cargo:rustc-check-cfg=cfg(no_literal_c_string)
+cargo:rustc-check-cfg=cfg(no_source_text)
+cargo:rustc-check-cfg=cfg(proc_macro_span)
+cargo:rustc-check-cfg=cfg(proc_macro_span_file)
+cargo:rustc-check-cfg=cfg(proc_macro_span_location)
+cargo:rustc-check-cfg=cfg(procmacro2_backtrace)
+cargo:rustc-check-cfg=cfg(procmacro2_build_probe)
+cargo:rustc-check-cfg=cfg(procmacro2_nightly_testing)
+cargo:rustc-check-cfg=cfg(procmacro2_semver_exempt)
+cargo:rustc-check-cfg=cfg(randomize_layout)
+cargo:rustc-check-cfg=cfg(span_locations)
+cargo:rustc-check-cfg=cfg(super_unstable)
+cargo:rustc-check-cfg=cfg(wrap_proc_macro)
+cargo:rerun-if-changed=src/probe/proc_macro_span.rs
+cargo:rustc-cfg=wrap_proc_macro
+cargo:rerun-if-changed=src/probe/proc_macro_span_location.rs
+cargo:rustc-cfg=proc_macro_span_location
+cargo:rerun-if-changed=src/probe/proc_macro_span_file.rs
+cargo:rustc-cfg=proc_macro_span_file
+cargo:rerun-if-env-changed=RUSTC_BOOTSTRAP

backend/target/debug/build/proc-macro2-cdc80bb011340cc8/root-output

@@ -0,0 +1 @@
+/home/alvis/taskpile/backend/target/debug/build/proc-macro2-cdc80bb011340cc8/out