codify "platform" into resolution logic, server-fn/fullstack overhaul (#4596)

overhaul dioxus fullstack using a new implementation of server_fn

This PR is a complete rewrite of dioxus fullstack designed to improve compatibility with axum and to fix a number of compilation errors based on feature flag unification plumbing through macros.

packages/fullstack-core/Cargo.toml

@@ -0,0 +1,42 @@
+[package]
+name = "dioxus-fullstack-core"
+authors = ["Jonathan Kelley", "Evan Almloff"]
+version = { workspace = true }
+edition = "2021"
+description = "Hooks for serializing futures, values in dioxus-fullstack and other utilities"
+license = "MIT OR Apache-2.0"
+repository = "https://github.com/DioxusLabs/dioxus/"
+homepage = "https://dioxuslabs.com"
+keywords = ["web", "gui", "server"]
+resolver = "2"
+
+[dependencies]
+dioxus-core = { workspace = true, features = ["serialize"]}
+dioxus-signals = { workspace = true }
+dioxus-hooks = { workspace = true }
+futures-channel = { workspace = true }
+serde = { workspace = true }
+dioxus-history = { workspace = true }
+dioxus-document = { workspace = true }
+ciborium = { workspace = true }
+base64 = { workspace = true }
+tracing = { workspace = true }
+thiserror = { workspace = true }
+axum-core = { workspace = true }
+http = { workspace = true }
+anyhow = { workspace = true }
+inventory = { workspace = true }
+serde_json = { workspace = true }
+generational-box = { workspace = true }
+futures-util = { workspace = true, features = ["std"] }
+
+[features]
+web = []
+server = []
+
+[dev-dependencies]
+dioxus-fullstack = { workspace = true }
+dioxus = { workspace = true, features = ["fullstack"] }
+
+[package.metadata.docs.rs]
+cargo-args = ["-Zunstable-options", "-Zrustdoc-scrape-examples"]