Import bulk of code from River UI project

Here, import the framework code from the River UI project at [1].

I've added some READMEs, configuration files, etc., but otherwise very
little has changed. There are a couple small things like adding `printf`
variants for errors (which we'll need for Go 1.24 because it doesn't let
you pass only a message to a printf-like function, and removing errors
for specific types like jobs/queues/workflows (those will like in River
UI instead).

[1] https://github.com/riverqueue/riverui/tree/master/internal

Author: brandur

.github/workflows/ci.yaml

@@ -0,0 +1,47 @@
+name: CI
+
+on:
+  push:
+    branches:
+      - master
+  pull_request:
+
+jobs:
+  build_and_test:
+    runs-on: ubuntu-latest
+
+    steps:
+      - name: Checkout
+        uses: actions/checkout@v4
+
+      - name: Setup Go
+        uses: actions/setup-go@v5
+        with:
+          check-latest: true
+          go-version-file: "go.mod"
+
+      - name: Display Go version
+        run: go version
+
+      - name: Test
+        run: make test
+
+  golangci-lint:
+    runs-on: ubuntu-latest
+    env:
+      GOLANGCI_LINT_VERSION: v1.64.6
+
+    steps:
+      - name: Checkout
+        uses: actions/checkout@v4
+
+      - name: Setup Go
+        uses: actions/setup-go@v5
+        with:
+          check-latest: true
+          go-version-file: "go.mod"
+
+      - name: Lint
+        uses: golangci/golangci-lint-action@v6
+        with:
+          version: ${{ env.GOLANGCI_LINT_VERSION }}

.golangci.yaml

@@ -0,0 +1,96 @@
+issues:
+  exclude:
+    - 'Error return value of .(\w+\.Rollback(.*)). is not checked'
+
+linters:
+  presets:
+    - bugs
+    - comment
+    - format
+    - performance
+    - style
+    - test
+    - unused
+
+  disable:
+    # disabled, but which we should enable with discussion
+    - wrapcheck # checks that errors are wrapped; currently not done anywhere
+
+    # disabled because we're not compliant, but which we should think about
+    - exhaustruct # checks that properties in structs are exhaustively defined; may be a good idea
+    - testpackage # requires tests in test packages like `river_test`
+
+    # disabled because they're annoying/bad
+    - interfacebloat # we do in fact want >10 methods on the Adapter interface or wherever we see fit.
+    - godox # bans TODO statements; total non-starter at the moment
+    - err113 # wants all errors to be defined as variables at the package level; quite obnoxious
+    - mnd # detects "magic numbers", which it defines as any number; annoying
+    - ireturn # bans returning interfaces; questionable as is, but also buggy as hell; very, very annoying
+    - lll # restricts maximum line length; annoying
+    - nlreturn # requires a blank line before returns; annoying
+    - wsl # a bunch of style/whitespace stuff; annoying
+
+linters-settings:
+  depguard:
+    rules:
+      all:
+        files: ["$all"]
+        deny:
+          - desc: "Use `github.com/google/uuid` package for UUIDs instead."
+            pkg: "github.com/xtgo/uuid"
+
+  forbidigo:
+    forbid:
+      - msg: "Use `require` variants instead."
+        p: '^assert\.'
+      - msg: "Use `Func` suffix for function variables instead."
+        p: 'Fn\b'
+      - msg: "Use built-in `max` function instead."
+        p: '\bmath\.Max\b'
+      - msg: "Use built-in `min` function instead."
+        p: '\bmath\.Min\b'
+
+  gci:
+    sections:
+      - Standard
+      - Default
+      - Prefix(github.com/riverqueue)
+
+  gomoddirectives:
+    replace-local: true
+
+  gosec:
+    excludes:
+      - G404 # use of non-crypto random; overly broad for our use case
+
+  revive:
+    rules:
+      - name: unused-parameter
+        disabled: true
+
+  tagliatelle:
+    case:
+      rules:
+        json: snake
+
+  testifylint:
+    enable-all: true
+    disable:
+      - go-require
+
+  varnamelen:
+    ignore-names:
+      - db
+      - eg
+      - f
+      - i
+      - id
+      - j
+      - mu
+      - r
+      - sb # common convention for string builder
+      - t
+      - tt # common convention for table tests
+      - tx
+      - w
+      - wg

Makefile

@@ -0,0 +1,23 @@
+.DEFAULT_GOAL := help
+
+# Looks at comments using ## on targets and uses them to produce a help output.
+.PHONY: help
+help: ALIGN=22
+help: ## Print this message
+	@awk -F '::? .*## ' -- "/^[^':]+::? .*## /"' { printf "'$$(tput bold)'%-$(ALIGN)s'$$(tput sgr0)' %s\n", $$1, $$2 }' $(MAKEFILE_LIST)
+
+.PHONY: lint
+lint:: ## Run linter
+	golangci-lint run --fix
+
+.PHONY: test
+test:: ## Run test suite
+	go test ./...
+
+.PHONY: test/race
+test/race:: ## Run test suite with race detector
+	go test ./... -race
+
+.PHONY: tidy
+tidy:: ## Run `go mod tidy`
+	go mod tidy