Updates to non-deterministic FTSP (#382)

## Description

This PR adds some features to the non-deterministic fault-tolerant state
preparation synthesis and simulations.
Changes:

- The idle noise parameter can now be defined explicitly in the
construction of the `NoisyNDFTStatePrepSimulator`.
- Added more optimized constructions for flag fault-tolerant stabilizer
measurements.
- Added circuits and evaluations for the state preparation of the d=7
square-octagon color code.

## Checklist:

<!---
This checklist serves as a reminder of a couple of things that ensure
your pull request will be merged swiftly.
-->

- [x] The pull request only contains commits that are related to it.
- [x] I have added appropriate tests and documentation.
- [x] I have made sure that all CI jobs on GitHub pass.
- [x] The pull request introduces no new warnings and follows the
project's style guidelines.

---------

Co-authored-by: pre-commit-ci[bot] <66853113+pre-commit-ci[bot]@users.noreply.github.com>

Author: pehamTom

docs/StatePrep.ipynb

@@ -137,8 +137,8 @@
    "source": [
     "ps = [0.1, 0.05, 0.01, 0.008, 0.006, 0.004, 0.002, 0.001]\n",
     "\n",
-    "non_ft_simulator.plot_state_prep(ps, min_errors=50, name=\"non-FT\")\n",
-    "ft_simulator.plot_state_prep(ps, min_errors=50, name=\"FT\")"
+    "non_ft_simulator.plot_state_prep(ps, min_errors=50, name=\"non-FT\", p_idle_factor=0.01)\n",
+    "ft_simulator.plot_state_prep(ps, min_errors=50, name=\"FT\", p_idle_factor=0.01)"
    ]
   },
   {
@@ -245,12 +245,14 @@
    "metadata": {},
    "outputs": [],
    "source": [
-    "cc_simulator = NoisyNDFTStatePrepSimulator(cc_ft_sp, code=cc, zero_state=True, p=p)\n",
+    "cc_simulator = NoisyNDFTStatePrepSimulator(cc_ft_sp, code=cc, zero_state=True)\n",
     "\n",
-    "ps = [0.1, 0.05, 0.01, 0.008, 0.006, 0.004, 0.002, 0.001, 0.0008, 0.0006, 0.0004, 0.0003]\n",
+    "ps = [0.1, 0.05, 0.04, 0.03, 0.02, 0.01, 0.009, 0.008]\n",
     "\n",
-    "ft_simulator.plot_state_prep(ps, min_errors=50, name=\"Distance 3\")  # simulate Steane code as comparison\n",
-    "cc_simulator.plot_state_prep(ps, min_errors=50, name=\"Distance 5\")"
+    "ft_simulator.plot_state_prep(\n",
+    "    ps, min_errors=50, name=\"Distance 3\", p_idle_factor=0.01\n",
+    ")  # simulate Steane code as comparison\n",
+    "cc_simulator.plot_state_prep(ps, min_errors=50, name=\"Distance 5\", p_idle_factor=0.01)"
    ]
   },
   {
@@ -418,7 +420,7 @@
  ],
  "metadata": {
   "kernelspec": {
-   "display_name": "venv3_12",
+   "display_name": "Python 3 (ipykernel)",
    "language": "python",
    "name": "python3"
   },