Correct DevFlow schemas and specs to match existing runtime

[mattleibow]

Scope

Schema/spec corrections only. No runtime, client, CLI, API, or behavior changes. All 12 changed files are under docs/DevFlow/spec/.

This is the bottom layer of the requested replacement stack for #651. The clean starting commit was exactly its recorded pre-implementation base, 64e8e90c6921e68cdb2747530b58dd528dd57578; all evidence below comes from that baseline, not the feature implementation.

Existing-contract corrections

Previous claim	Existing runtime fact	Baseline evidence
Contexts are a bare array/contexts, active only; metadata missing/non-null URL	{webviews:[...]} includes inactive/not-ready registrations, nullable URL, index/automationId/isReady/active; IDs use existing registration aliases	DevFlowAgentService.Handlers.cs:195–243,2295–2316
Evaluate accepts a top-level expression; DOM is JSON; context selection/errors/actions incomplete	Raw CDP method/params and raw responses; DOM/source are HTML; existing query/body alias precedence, action metadata, and {success:false,error} 400/404 responses	DevFlowAgentService.Handlers.cs:1853–1856,1965–2243,2319–2356
WebView network captures browser requests; screenshots support JPEG	/webview/network remains the existing HTTP 200 native .NET network-store alias, not browser fetch/XHR or a new 501. WebView capture is native-first/CDP fallback; both screenshot routes return PNG	DevFlowAgentService.Handlers.cs:2245–2293; Core screenshot :1983; Native :470
Logs use verbose properties/restricted lowercase severity/source; headers are scalar strings	Logs serialize t/l/c/m/e/s, preserve producer-defined level/source; headers contain arrays of values	FileLogEntry.cs:9–14; NetworkRequestEntry.cs:59,63,147–162
Universal WebSocket data envelope, severity-filtered logs, nested details command	Network/log entries are top-level; get_details reads top-level id and may return null; clear produces an existing error; logs filter source/replay only	DevFlowAgentService.Handlers.cs:1382–1581
Sensor examples use lowercase x/y/z and omit emitted fields; stopped event advertised	Sensor values use X/Y/Z/W and actual compass/barometer names; readings emit sensor/data plus compatibility reading; subscription includes sensorName/throttleMs; no stopped notification is emitted	SensorManager.cs:199–218,272–308; EssentialsAgentSupport.cs:696–798
Profiler emits individual samples/marker/span events and camelCase DTOs; threadId is string	Events are batch/stopped/error; DTOs retain PascalCase; ThreadId is nullable integer; existing capabilities/current/limit documented	DevFlowAgentService.Handlers.cs:722–740,1583–1720; ProfilerContracts.cs:3–79
Profiler start/stop return bare DTOs and publish requests require server-owned output fields	Correct session wrappers, optional start body/range 50–60000, name-only marker/span inputs, and existing errors	DevFlowAgentService.Handlers.cs:768–868
UI subscription requires timestamp/generic filter; typed client belongs to Driver	UI consumes type/data.events, not timestamp/filter; AgentClient lives in portable Client and is forwarded by Driver	DevFlowAgentService.Handlers.cs:1061–1104; Client project and Driver type forwards

Why the casing changes are corrections

• fps → Fps: baseline ProfilerSample.Fps has no JSON-name override; the default serializer preserves that name. An actual baseline batch emitted Fps.
• x → X: baseline sensor writer explicitly writes X, Y, Z.
• level → l: baseline FileLogEntry explicitly declares [JsonPropertyName("l")]. HTTP/WS payloads already use that compact key.

No hostKind, new webview-<index> IDs, owner correlation, includeWebViewElements, compatibility removal, or lockstep-version implementation is included. Existing aliases (including ready/isReady) are preserved/documented.

Validation

dotnet test src/DevFlow/Microsoft.Maui.DevFlow.Tests/Microsoft.Maui.DevFlow.Tests.csproj \
  --no-restore \
  --filter 'FullyQualifiedName~ProtocolSpecTests|FullyQualifiedName~CdpWebViewNavigationTests|FullyQualifiedName~CdpWebViewRegistryTests' \
  --verbosity quiet

9 passed. A local, artifact-only probe exercised the pinned baseline handlers/serializers and recorded 37 HTTP/WS payloads; semantic validation parsed 32 spec documents, passed 67 payload/schema checks, and rejected 10 obsolete shapes. git diff --check passes. No packages or tooling were added. CDP/native screenshot seams and controlled sensor values were used; no device/hardware coverage is claimed.

Separate audit findings

This coherent correction slice is not a claim of complete protocol conformance. Verified follow-ups are recorded separately: agent-status fields, UI query/tree options and screenshot aliases/defaults, device/sensor-list shapes and enum casing, remaining general error schemas, and distributed debug/setup docs claiming a nonexistent Blazor JS initializer. The detailed 30-row evidence matrix and payload/probe artifacts are retained in the owning session rather than adding tracking Markdown or broader onboarding rewrites to this PR.