ci: remove .cirrus.yml

diff --git a/.cirrus.yml b/.cirrus.yml
deleted file mode 100644
index 33e49c18..00000000
--- a/.cirrus.yml
+++ /dev/null
@@ -1,199 +0,0 @@
-env:  # Global defaults
-  CIRRUS_CLONE_DEPTH: 1
-  CIRRUS_LOG_TIMESTAMP: true
-  MAKEJOBS: "-j10"
-  TEST_RUNNER_PORT_MIN: "14000"  # Must be larger than 12321, which is used for the http cache. See https://cirrus-ci.org/guide/writing-tasks/#http-cache
-  CI_FAILFAST_TEST_LEAVE_DANGLING: "1"  # Cirrus CI does not care about dangling processes and setting this variable avoids killing the CI script itself on error
-
-# A self-hosted machine(s) can be used via Cirrus CI. It can be configured with
-# multiple users to run tasks in parallel. No sudo permission is required.
-#
-# https://cirrus-ci.org/guide/persistent-workers/
-#
-# Generally, a persistent worker must run Ubuntu 23.04+ or Debian 12+.
-#
-# The following specific types should exist, with the following requirements:
-# - small: For an x86_64 machine, with at least 2 vCPUs and 8 GB of memory.
-# - medium: For an x86_64 machine, with at least 4 vCPUs and 16 GB of memory.
-# - arm64: For an aarch64 machine, with at least 2 vCPUs and 8 GB of memory.
-#
-# CI jobs for the latter configuration can be run on x86_64 hardware
-# by installing qemu-user-static, which works out of the box with
-# podman or docker. Background: https://stackoverflow.com/a/72890225/313633
-#
-# The above machine types are matched to each task by their label. Refer to the
-# Cirrus CI docs for more details.
-#
-# When a contributor maintains a fork of the repo, any pull request they make
-# to their own fork, or to the main repository, will trigger two CI runs:
-# one for the branch push and one for the pull request.
-# This can be avoided by setting SKIP_BRANCH_PUSH=true as a custom env variable
-# in Cirrus repository settings, accessible from
-# https://cirrus-ci.com/github/my-organization/my-repository
-#
-# On machines that are persisted between CI jobs, RESTART_CI_DOCKER_BEFORE_RUN=1
-# ensures that previous containers and artifacts are cleared before each run.
-# This requires installing Podman instead of Docker.
-#
-# Futhermore:
-# - podman-docker-4.1+ is required due to the bugfix in 4.1
-#   (https://github.com/bitcoin/bitcoin/pull/21652#issuecomment-1657098200)
-# - The ./ci/ dependencies (with cirrus-cli) should be installed. One-liner example
-#   for a single user setup with sudo permission:
-#
-#   ```
-#   apt update && apt install git screen python3 bash podman-docker uidmap slirp4netns curl -y && curl -L -o cirrus "https://github.com/cirruslabs/cirrus-cli/releases/latest/download/cirrus-linux-$(dpkg --print-architecture)" && mv cirrus /usr/local/bin/cirrus && chmod +x /usr/local/bin/cirrus
-#   ```
-#
-# - There are no strict requirements on the hardware. Having fewer CPU threads
-#   than recommended merely causes the CI script to run slower.
-#   To avoid rare and intermittent OOM due to short memory usage spikes,
-#   it is recommended to add (and persist) swap:
-#
-#   ```
-#   fallocate -l 16G /swapfile_ci && chmod 600 /swapfile_ci && mkswap /swapfile_ci && swapon /swapfile_ci && ( echo '/swapfile_ci none swap sw 0 0' | tee -a /etc/fstab )
-#   ```
-#
-# - To register the persistent worker, open a `screen` session and run:
-#
-#   ```
-#   RESTART_CI_DOCKER_BEFORE_RUN=1 screen cirrus worker run --labels type=todo_fill_in_type --token todo_fill_in_token
-#   ```
-
-# https://cirrus-ci.org/guide/tips-and-tricks/#sharing-configuration-between-tasks
-filter_template: &FILTER_TEMPLATE
-  # Allow forks to specify SKIP_BRANCH_PUSH=true and skip CI runs when a branch is pushed,
-  # but still run CI when a PR is created.
-  # https://cirrus-ci.org/guide/writing-tasks/#conditional-task-execution
-  skip: $SKIP_BRANCH_PUSH == "true" && $CIRRUS_PR == ""
-  stateful: false  # https://cirrus-ci.org/guide/writing-tasks/#stateful-tasks
-
-base_template: &BASE_TEMPLATE
-  << : *FILTER_TEMPLATE
-  merge_base_script:
-    # Require git (used in fingerprint_script).
-    - git --version || ( apt-get update && apt-get install -y git )
-    - if [ "$CIRRUS_PR" = "" ]; then exit 0; fi
-    - git fetch --depth=1 $CIRRUS_REPO_CLONE_URL "pull/${CIRRUS_PR}/merge"
-    - git checkout FETCH_HEAD  # Use merged changes to detect silent merge conflicts
-                               # Also, the merge commit is used to lint COMMIT_RANGE="HEAD~..HEAD"
-
-main_template: &MAIN_TEMPLATE
-  timeout_in: 120m  # https://cirrus-ci.org/faq/#instance-timed-out
-  ci_script:
-    - ./ci/test_run_all.sh
-
-global_task_template: &GLOBAL_TASK_TEMPLATE
-  << : *BASE_TEMPLATE
-  << : *MAIN_TEMPLATE
-
-compute_credits_template: &CREDITS_TEMPLATE
-  # https://cirrus-ci.org/pricing/#compute-credits
-  # Only use credits for pull requests to the main repo
-  use_compute_credits: $CIRRUS_REPO_FULL_NAME == 'bitcoin/bitcoin' && $CIRRUS_PR != ""
-
-task:
-  name: 'lint'
-  << : *BASE_TEMPLATE
-  container:
-    dockerfile: ci/lint_imagefile
-    cpu: 1
-    memory: 1G
-  # For faster CI feedback, immediately schedule the linters
-  << : *CREDITS_TEMPLATE
-  unshallow_script:
-    - git fetch --unshallow --no-tags
-  lint_script:
-    - ./ci/lint_run.sh
-
-task:
-  name: 'tidy'
-  << : *GLOBAL_TASK_TEMPLATE
-  persistent_worker:
-    labels:
-      type: medium
-  env:
-    FILE_ENV: "./ci/test/00_setup_env_native_tidy.sh"
-
-task:
-  name: 'ARM, unit tests, no functional tests'
-  << : *GLOBAL_TASK_TEMPLATE
-  persistent_worker:
-    labels:
-      type: arm64  # Use arm64 worker to sidestep qemu and avoid a slow CI: https://github.com/bitcoin/bitcoin/pull/28087#issuecomment-1649399453
-  env:
-    FILE_ENV: "./ci/test/00_setup_env_arm.sh"
-
-task:
-  name: 'CentOS, depends, gui'
-  << : *GLOBAL_TASK_TEMPLATE
-  persistent_worker:
-    labels:
-      type: small
-  env:
-    FILE_ENV: "./ci/test/00_setup_env_native_centos.sh"
-
-task:
-  name: 'previous releases, depends DEBUG'
-  << : *GLOBAL_TASK_TEMPLATE
-  persistent_worker:
-    labels:
-      type: small
-  env:
-    FILE_ENV: "./ci/test/00_setup_env_native_previous_releases.sh"
-
-task:
-  name: 'TSan, depends, no gui'
-  << : *GLOBAL_TASK_TEMPLATE
-  persistent_worker:
-    labels:
-      type: medium
-  env:
-    FILE_ENV: "./ci/test/00_setup_env_native_tsan.sh"
-
-task:
-  name: 'MSan, depends'
-  << : *GLOBAL_TASK_TEMPLATE
-  persistent_worker:
-    labels:
-      type: small
-  timeout_in: 300m  # Use longer timeout for the *rare* case where a full build (llvm + msan + depends + ...) needs to be done.
-  env:
-    FILE_ENV: "./ci/test/00_setup_env_native_msan.sh"
-
-task:
-  name: 'fuzzer,address,undefined,integer, no depends'
-  << : *GLOBAL_TASK_TEMPLATE
-  persistent_worker:
-    labels:
-      type: medium
-  timeout_in: 240m  # larger timeout, due to the high CPU demand
-  env:
-    FILE_ENV: "./ci/test/00_setup_env_native_fuzz.sh"
-
-task:
-  name: 'no IPC, i686, DEBUG'
-  << : *GLOBAL_TASK_TEMPLATE
-  persistent_worker:
-    labels:
-      type: medium
-  env:
-    FILE_ENV: "./ci/test/00_setup_env_i686_no_ipc.sh"
-
-task:
-  name: 'no wallet, libbitcoinkernel'
-  << : *GLOBAL_TASK_TEMPLATE
-  persistent_worker:
-    labels:
-      type: small
-  env:
-    FILE_ENV: "./ci/test/00_setup_env_native_nowallet_libbitcoinkernel.sh"
-
-task:
-  name: 'macOS-cross, gui, no tests'
-  << : *GLOBAL_TASK_TEMPLATE
-  persistent_worker:
-    labels:
-      type: small
-  env:
-    FILE_ENV: "./ci/test/00_setup_env_mac_cross.sh"