Replace the old Lisp-like array expression representation
(["AND", ["PARAM", ...], ...]) with a class hierarchy rooted in
an abstract Expression class (Literal, Parameter, Binary, Unary,
FunctionCall, Conditional). This gives compile-time type safety
to expression construction, evaluation, and pattern matching.
Key changes:
- New lib/common/expression.ts defines the class hierarchy with
map/evaluate/toString methods
- Rewrite parser as hand-rolled recursive descent, removing the
parsimmon dependency
- Extend Path with a colon separator to unify parameter identity
and attributes into a single address space (e.g.
"Device.WiFi.SSID.1.Name:writable"). The colon field tracks
how many trailing segments are attribute qualifiers. PathSet
rewritten with separate param/attr segment indexes
- Flatten device attribute representation in the UI to
colon-delimited keys mirroring the new path syntax
